Aims

The aim of this study was to report the outcomes of different treatment options for glenoid loosening following reverse shoulder arthroplasty (RSA) at a minimum follow-up of two years.

We hypothesised that a large acromial cover with an upwardly tilted glenoid fossa would be associated with degenerative rotator cuff tears (RCTs), and conversely, that a short acromion with an inferiorly inclined glenoid would be associated with glenohumeral osteoarthritis (OA). This hypothesis was tested using a new radiological parameter, the critical shoulder angle (CSA), which combines the measurements of inclination of the glenoid and the lateral extension of the acromion (the acromion index).

The CSA was measured on standardised radiographs of three groups: 1) a control group of 94 asymptomatic shoulders with normal rotator cuffs and no OA; 2) a group of 102 shoulders with MRI-documented full-thickness RCTs without OA; and 3) a group of 102 shoulders with primary OA and no RCTs noted during total shoulder replacement. The mean CSA was 33.1° (26.8° to 38.6°) in the control group, 38.0° (29.5° to 43.5°) in the RCT group and 28.1° (18.6° to 35.8°) in the OA group. Of patients with a CSA > 35°, 84% were in the RCT group and of those with a CSA < 30°, 93% were in the OA group.

We therefore concluded that primary glenohumeral OA is associated with significantly smaller degenerative RCTs with significantly larger CSAs than asymptomatic shoulders without these pathologies. These findings suggest that individual quantitative anatomy may imply biomechanics that are likely to induce specific types of degenerative joint disorders.

Cite this article: Bone Joint J 2013;95-B:935–41.

Background

In elderly patients with complex proximal humerus fractures and osteoporotic bone reconstruction is not always possible. Although hemiarthroplasty is an alternative, non-union or tuberosity migration can lead to inferior functional results. Implantation of a Reverse Total Shoulder Arthroplasty (RTSA) seems to be an interesting alternative. In the present study we retrospectively analyzed the short-term results of RTSA for complex proximal humerus fractures in the elderly.

Introduction

Following tear of its tendon, the muscle undergoes retraction, atrophy and fatty infiltration. These changes are inevitable and considered irreversible and limit the potential of successful repair of musculotendinous units. It was the purpose of this study to test the hypothesis that administration of anabolic steroids can prevent these muscular changes following experimental supraspinatus tendon release in the rabbit.

Introduction: Additional tendon length is occasionally needed for the surgical reattachment of retracted tendons and for lengthening of intact but contracted tendons. To achieve additional length with the known techniques such as the z-plasty, the tendon needs to be cut through entirely and loses its continuity. The purpose of this study was to develop a new method for tendon lengthening, where continuity is preserved and a high amount of additional length is achievable.

Methods: Calf Achilles tendons (n=35) were harvested immediately after slaughter and 5 tendons were assigned to groups I to VII. Angles of 60° (group I and IV), 45° (group II and V) and 30° (group III and VI) were cut. In group IV to VI mattress suture stitches were made along the cutting lines. The mean length increase of the helical cuts was used to define the intended length of group VII, where a z-plasty was performed. Maximal tensile force (Fmax) and additional achieved lengthening at Fmax (LFmax) were determined for each tendon using a materials testing machine. Data were statistically analyzed using ANOVA for inter-group differences and Spearman-correlation for cut angle to additional length relations at a significance level of p< 0.05.

Results: Tendons which were cut helically and sutured (group IV to VI) could achieve higher Fmax than the helically cut tendons without suturing (group I to III). The length and tensile force could be partially controlled by choice of the angle of the helical cut; In the groups for which the cut tendons were not sutured, LFmax was negatively correlated to the cut angle (r=−0.66, p=0.010) and positively correlated to the Fmax (r=0.72, p=0.003). If the helical cut tendons were sutured, there was no correlation of LFmax and cut angle (r=−0.01, p=0.96), but strong positive correlation of Fmax and cut angle (r=0.89, p< 0.0001). Helical cut tendon could achieve higher amount of additional length and tensile strength than tendons lengthened using z-plasty; in group VII, a LFmax of 72%±10% was achieved by a Fmax of 70N±15N. Other than in groups III and IV, where the cut angle was 30°, resulting in 179%±80% and 113%±10%, respectively, significant higher tensile force capacities (from a minimum of 80N±54N in group II to maximally 222N±62N in group IV) was achieved.

Discussion: Helical cutting of tendons allows lengthening tendons to an amount not possible with conventional methods. The lengthened coil-shaped tendon remains in continuity and has the potential to withstand considerable loads also without additional suture reinforcement. The behavior of the helical cut tendon in vivo is not known. However, the preservation of continuity might be favorable not only in regard to high tensile forces but also to healing.

Background: Progression of fatty infiltration of the suscapularis muscle subsequent to total shoulder arthroplasty is frequent and may be an underestimated problem. The approach with osteotomy of the lesser tuberosity led to consistent bone to bone healing with neither retraction nor overtensioning of the musculotendinous unit. However, in a previous study, fatty infiltration of the subscapular muscle had progressed at least by one stage in 45% of the patients’ shoulders. We hypothesized that anterior approach to the shoulder joint with release of the subscapularis muscle would lead to a direct or indirect subclinical damage of the subscapular nerve and would be an explanation for the progression of fatty infiltration of the muscle.

Methods: Nine Shoulders in eight consecutive patients had received a total shoulder arthroplasty using an anterior approach with osteotomy of the lesser tuberosity. The mean age at time of operation was 67 years. Patients were followed clinically including the Constant score and a detailed neurological examination, as well as radiographically with pre–and postoperative MRI’s, CT’s and standard radiographs at 6–and 12 months thereafter. Neurophysiological assessment was performed using a new pre–intra–and postoperative electromyographic technique for the subscapular muscle. Fibrillation and sharp waves as spontaneuous activities of the motor unit potentials (MUP) indicated direct signs of denervation. Incomplete interference patterns (IP’s) indicated an incomplete innervation pattern as an indirect sign of denervation.

Results: After a one year follow up, 89% of the patients were very satisfied or satisfied with the result. The relative Constant Score improved from an average of 50 percent preoperatively to an average of 96 percent postoperatively (p=0,008). That corresponds to a postoperative subjective Shoulder value of 89 percent. From preoperative to 6–and 12-months postoperative, the average degree of fatty infiltration of the subscapular muscle progressed in an almost significant extent (0.6, 1.1, and 1.6 respectively; p=0.056).

Intra–and postoperatively, there were neither fibrillations and sharp waves of the MUP’s as direct signs, nor incomplete (IP’s) of the motor unit of the subscapular nerve as indirect signs of denervation.

Conclusion: Total Shoulder Arthroplasties perfomed by an anterior approach using an osteotomy of the lesser tuberosity yields good results with a high satisfaction rate. Comparable to our previous study, there are signs of progression of fatty infiltration of the subscapularis muscle within the first year subsequent to total shoulder arthroplasty. However, there were no signs of direct or indirect subclinical damage of the subscapular nerve during total shoulder arthroplasty.

A significant portion of prosthetic joint infections with biofilm-embedded bacteria may not be adequately sampled by standard periprosthetic tissue collection techniques. The aim of the present study was to combine ultrasonication sampling procedures with standard in-traoperative sampling and cultural techniques.

A total of 69 patients with implants to be removed were included in this study; a prosthetic joint infection was diagnosed or rejected according to a standardized clinical score. Intra-operative tissue specimens were cultured using standard techniques; implants were subjected to ultrasonication and sonicates used for inoculation of cultures and broad-range eubacterial PCR.

According to the clinical score, a prosthetic joint infection was present in 14 of the 69 patients. 11/14 had positive cultures for tissue samples, 13/14 had positive cultures when considering in addition the results from sonicate cultures. Sonicate PCR was positive in 12/13, and negative in 1/13 (excluding one infection due to Candida albicans). Ultrasonication improved sensitivity of culture from 78.6% to 92.9%; sensitivity and specificity of PCR from sonicates was 92,3% and 100%, respectively.

Combined with serially sampled periprosthetic tissue, ultrasonication of implants may help to increase the sensitivity of laboratory investigations based on cultural procedures. PCR analyses did not improve sensitivity although implementation of PCR may aid in improving the specificity of cultural detection.

INTRODUCTION: Chronic experimental rotator cuff tears are associated with muscle retraction, atrophy, fatty infiltration, a pronounced change in the pennation angle of the muscle and consequent shortening of muscle fibres. It was the purpose of this investigation to study whether slow, continuous elongation of the musculotendinous unit can revert the pennation angle and elongate the shortened muscle fibres.

MATERIAL AND METHODS: The infraspinatus tendons of twelve sheep were released. After retraction of the tenotomised musculotendinous unit, the infra-spinatus was elongated one mm per day using a new elongation-apparatus. After restoring the approximate original length, the tendon was repaired back. Muscular architecture (retraction and pennation angle), fatty infiltration (in Hounsfield units=HU) and muscular cross sectional area (in % of the mean control side) were analyzed at start, at the time before elongation, at the time of repair and six and eighteen weeks thereafter.

RESULTS: In four sheep the elongation failed technically. In the other eight sheep, elongation could be achieved as planned. After retraction of 29mm ± 6 mm after 16 weeks (14% of original length, p=0.008), the mean traction time was 24 days ± 6 days with a mean traction distance of 19 mm ± 4 mm. At sacrifice the mean pennation angle increased in the failed sheep from 30° ± 6° up to 55° ± 14° (p=0.035). In those sheep in which traction was applied, the mean pennation angle was not different to the control side (29.8° ± 7.5° vs. 30° ± 6°, p=0.575). Compared to preoperative, there was a significant increase in fatty infiltration (36 HU, p=0.0001) and decrease of the muscular cross sectional area of 43 % (range 21% to 67%, p=0.0001) at 4 months. In the sheep in which traction could be achieved, fatty infiltration remain unchanged (36 HU ± 6 HU vs 38 HU ± 4 HU, p=0.438) and atrophy decreased by 22% (range 10% to 33%) after 6 weeks of continuous traction (p=0.008).

CONCLUSION: Continuous experimental elongation of a retracted musculotendinous unit is technically feasible and might lead to recovery of the muscle architecture, partial reversibility of atrophy and, arrest of progression of fatty infiltration.

INTRODUCTION: In irreparable rotator cuff tear associated with pseudoparalysis, inverse prostheses have shown to be able to restore overhead elevation and strength. If the rotator cuff disease involves the teres minor muscle, pseudoparalysis in external rotation can adversely affect function and functional outcome of inverse arthroplasty. The goal of our study was to evaluate the outcome of inverse total shoulder arthroplasty combined with latissimus dorsi transfer for combined pseudoparalysis in elevation and external rotation.

MATERIAL AND METHODS: From 1998 till 2005, we retrospectively analyzed 11 shoulders in 10 patients with at a mean follow up of 20 months. All 11 shoulders had a massive rotator cuff tear with fatty degeneration of the posterosuperior cuff including teres minor exceeding stage 2 according to Goutallier and an average osteoarthritis grade 2 according to Samilson and Prieto Data assessment included pre- and postoperative clinical examination and Constant Score as well as standard radiographs.

RESULTS At follow up, subjective shoulder value increased from 27% to 68%, Constant Score improved significantly from 48% to 94%, flexion from 106° to 141°, abduction from 95° to 150° and strength from 0.2 to 4.9 (p< 0.05). Although no gain was seen in active external rotation in adduction, a significant loss of external lag was noted from 47° to 9° (p< 0.05). All patients were able to perform overhead activities with increase in functional use of the arm (p< 0.05). Complication requiring revision included postoperative infection in one and hematoma in another case.

CONCLUSION: Irreparable rupture of the posterosuperior rotator cuff involving with pseudoparalysis of elevation and external rotation,, the implantation of an inverse prosthesis combined with latissimus dorsi transfer can increase active range of motion and substantially improve functional external rotation, as opposed to the published results of the inverse prosthesis alone, which do not improve active external rotation.

INTRODUCTION: The reverse DELTA III shoulder prosthesis can successfully relieve pain and restore function in cuff tear arthropathy. The most frequently reported complication is inferior scapular notching. The purpose of this study was to evaluate the clinical relevance of notching and to determine the anatomic and radiographic parameters that predispose to its occurrence.

STUDY PROTOCOL: Seventy-seven consecutive shoulders of 76 patients of an average age of 71 years with an irreparable rotator cuff deficiency were treated with a reverse DELTA III shoulder arthroplasty and followed clinically and radiographically under fluoroscopic control for a minimum of 24 months (mean: 44, range: 24 to 96). The effect of glenoid cranial caudal component positioning and of the prosthesis–scapular neck angle on the development of inferior scapular notching and clinical outcome was assessed.

RESULTS: All shoulders which developed notching did so in the first fourteen months. Forty-four percent of the shoulders had inferior scapular notching, 30% had posterior notching and anterior notching (8%) was rare. Osteophytes along the inferior scapula occurred in 27% of the shoulders. The angle between the glénosphère and the scapular neck (r=+0.677)) as well as the craniocaudal position of the glénosphère (r=+0.654) were highly correlated with inferior notching (p< 0.001). A notching index (notching index = height of prosthesis + (prosthesis scapular neck angle x 0.13) was calculated using the height of implantation of the glénosphère and the postoperative prosthesis scapular neck angle: This allowed a prediction of the occurrence of notching with a sensitivity of 91% and specificity of 88%. The height of implantation of the glenosphere had a greater influence on inferior notching than the prosthesis scapular neck angle by a factor of approximately 1:8. Inferior scapular notching was associated with a significantly poorer clinical outcome than absence of inferior notching: At final follow-up, the respective average subjective shoulder values were 62% and 71% (p=0.032), relative Constant scores were 72% and 83% (p=0.028), abduction strength was 4.3 versus 8.7 kilograms (p< 0.001), active abduction was 102° versus 118° (p=0.033) and flexion averaged 110° versus 127° (p=0.004).

DISCUSSION: Inferior scapular notching after reverse total shoulder arthroplasty adversely affects midterm clinical outcome. It can be prevented by optimal positioning of the glenoid component.

Background: It is commonly believed that rotator cuff tears do progress in size over time. Recent reports suggest that tear progression may not be necessarily true. It was the purpose of this study to review non-operatively treated isolated supraspinatus tears especially in terms of tear size progression.

Methods: Inclusion criteria were non-operatively treated isolated full-thickness tears of the supraspinatus, MRI at time of diagnosis available, and patients willing to undergo an additional MRI after more than 2 years after diagnosis. Twenty-four patients (20 men, 4 women) with an average at time diagnosis of 51 years identified and reviewed with MRI and clinically based on the Constant score.

Results: The average follow-up was 46 (27–87) months. The Constant score (not available at time of diagnosis) at follow-up averaged 75 points (relative Constant score 86%). Overall the average tear size did not change significantly over time (366mm2 at follow-up versus 393mm2 at time of diagnosis, p > 0.05). In 2 patients the tear was not detectable any longer on MRI suggesting that it was healed, in 7 patients the tear was smaller, in 10 patients it did not change over time and only in 5 patients it progressed.

Discussion and Conclusion: Non-operatively treated isolated supraspinatus tears were unchanged, smaller or even healed in 79% of the patients after a follow-up period of more than 4 years. This suggests that supra-spinatus tears do not necessarily progress over time and even have a potential to heal.

INTRODUCTION: Full thickness rotator cuff tears have been associated with changes of the anterior acromion. In a previous study we also documented differences in lateral extension of the acromion in rotator cuff tears compared with shoulders with intact cuffs. It was the purpose of this study to verify in a prospective examination, whether presence or absence of rotator cuff tearing in a precisely defined population is quantitatively related to the degree of lateral extension of the acromion.

MATERIAL AND METHODS: 59 consecutive patients between 60 and 70 years and hospitalized for reasons other than shoulder pathologies were entered into a prospective study. All 110 shoulders without previous operations, major trauma or rheumatoid arthritis were examined radiographically and with ultrasonography by two independent examiners.

RESULTS: 67 cuffs were intact, 28 showed a cuff tendinopathy, 17 a full thickness tearing. The acromion index for shoulder with rotator cuff tear was 0.75, for tendinopathy 0.68 and for normal cuffs 0.65. The differences between rotator cuff tears and the other two groups was significant (p< 0.05). The acromion index was not related to gender or osteoarthritis. An acromion index of < 0.77 had a positive predictive value of > 70%. An acromion index of < 0.7 predicted an absence of rotator cuff tearing with an accuracy of 97%. Interobserver agreement of the assessment was excellent with 88%.

CONCLUSION: The relationship between rotator cuff tears and a large extension of the acromion can be used to predict the presence of rotator cuff tears in shoulders between ages 60 and 70. A cause-effect relation is probable and will be studied further.

Purpose of the study: Muscles contract after a full thickness tear their tendon. The muscle then undergoes atrophy and fatty degeneration. These changes produce effects well described by histology, computed tomography and magnetic resonance imaging (MRI). To date however, the correlation of this process with the future conractile force of the muscle and the prognosis after cuff repain has been poorly understood.

Material and methods: Thirteen patients with a full thickness tear of the supraspinatus muscle were treated surgically by cuff suture. The shoulders were examined clinically and MRI. During the operation, the supra-scapular nerve was stimulated with a supramaximal voltage to obtain maximal muscle contraction which was measured. Biopsy specimens of the supraspinatus were taken before and after surgical repair in order to determine whether muscle activity during stimulation have any histological impact. The intraoperative measurements were compared with the MRI findings and the physical examination performed preoperative and at six weeks, six months and twelve months after surgery.

Results: Maximal force of the supraspinatus muscle was 200N, which is greater than the force of a direct suture repair. The maximal force was clearly correlated with muscle atrophy and fatty degeneration: by surface area, force was 12N/cm² for Goutallier grade 3 and 42 N/m² for grade 0. Five of the thirteen repairs ended with a secondary tear, the muscle in four of the five patients was among the six strongest muscles. The fifth case was the weakest muscle of all. The histological study revealed a larger quantity of lipofuchin in the muscle with atrophy and a change in the fiber structure. Analysis of the results did not demonstrate any lesions caused by the tension during the operation. MRI demonstrated one case of repair without secondary tear, the fatty infiltration had not improved and the atrophy only partially. In muscles with secondary tears, atrophy and fatty degeneration progressed significantly.

Discussion and conclusion: There is a risk of rupture of the supraspinatus tendon in the event of muscle atrophy but also for good quality muscle. The capacity of a muscle to develop force strongly depends on the state of atrophy and fatty degeneration. Atrophy can regress after reconstruction without secondary tear, but fatty degeneration is irreversible.

Purpose of the study: Chronic lateral instability of the ankle is often associated with residual varus deformity of the rear foot and exaggerated plantar flexion of the first ray. Several surgical techniques have been described to treat this problem, but recurrence can occur if all the components of the instability are not corrected. The purpose oft his work was to present was to present a new diagnostic and therapeutic approach to the treatment of recurrent lateral instability of the ankle.

Material and methods: Eight patients with talipes cavovarus(9 feet) were treated for recurrent chronic instability of the ankle. All patients had undergone at least one prior procedure to stabilize the rear foot and suffered persistent pain as well as subjective ankle instability. Mean age was 25 years. All patients underwent a calcaneal osteotomy for lateralization and transfer of the long fibular onto the short fibular ligament, with an additional Bronström ligament reconstruction in four cases. Clinical and radiological follow-up was 37 months on average.

Results: All patients were very satisfied. The AOFAS score improved from 58 points preoperatively to 97 points (max 100 points) at last follow-up. Postoperative alignment of the rear foot was considered physiological in all cases.

Conclusion: Recurrent chronic lateral instability of the ankle is often associated with chronic misalignment of the rear foot, leading to gait disorders and persistent pain. Ligament insufficiency, varus misalignment, and over-solicitation of the long fibular should be investigated and treated with an individually adapted surgical procedure in order to correct the recurrent instability. The results of this approach have been very promising and have been associated with very strong patient satisfaction.

Purpose of the study: Recurrent deformity in adulthood after successful treatment of clubfoot in childhood is exceptional. Patients experience subjective instability of the hindfood associated with progressive varus deformity and osteoarthritis of the subtalar joint. The purpose of this study was to analyze outcome after double arthrodesis in the specific situation.

Material and methods: Nine patients aged 41 years on average (range 18–64 years) were reviewed clinically and radiologically at mean 43 months follow-up after double arthrodesis (subtalar and Chopart). Time between the primary surgery and arthrodesis was 25 years on average (range 8–37 years). Clinical outcome was assessed with the AOFAS system. Plain x-rays were analyzed.

Results: The AOFAS score improved from 42 points preoperatively to 67 points on average at last follow-up (maximum 90 points). Improvement in pain was less pronounced, 27 points preoperatively and 13 points at last follow-up. Ankle motion did not decrease significantly. There was a non-significant progression of the ankle joint osteoarthritic degeneration in 71% of patients. Subjectively, the patients were moderately satisfied with the postoperative alignment of the hindfoot.

Conclusion: Double arthrodesis is often the only alternative for adults with recurrent clubfoot deformity causing pain and subjective instability of the hindfoot. The results in our series did not reveal any significant progression of the ankle joint degeneration at midterm follow-up of three years. Pain and subjective instability were improved, though the physiological alignment of the hindfoot could not be totally restored.

The practice of rotator cuff repair rapidly moves towards arthroscopic techniques especially for single tendon tears. Although the clinical results are relatively well established, the structural results of open rotator cuff repair and their correlation with the clinical outcome are poorly known. In order to provide a baseline for future studies using other repair techniques, this study was carried out to assess the structural changes in the repaired musculotendinous unit and to correlate these findings with the clinical outcome after rupture and repair of an isolated full thickness single tendon tear of the rotator cuff.

To prospectively assess the quality of an open rotator cuff tendon repair technique, to determine how structural changes of rotator cuff muscles are affected by tendon repair, and to correlate the structural results of MRI studies with the clinical outcome.

Direct open repair of a complete, isolated single tendon tear of the rotator cuff resulted in significant improvement in function and objective evidence of tendon healing on MRI. Successful direct repair was not associated with recovery of preoperative muscular atrophy or fatty infiltration when comparing Goutallier stage fatty infiltration between pre and postoperative patients.

The age and gender-adjusted Constant score increased significantly from an average of 63.9% preoperatively to 94.5% postoperatively (p< 0.0001). Pain improved significantly from 6.8 points to 13.2 points on a visual analogue scale. (p< 0.0001). Activities of daily living increased from 11.2 points preoperatively to 17.9 points postoperatively (p< 0.0001). Anterior elevation, abduction and internal rotation improved significantly for subscapularis and supraspinatus repairs, but there was no significant change in external rotation. The overall rerupture rate was 12.5%. There was no significant improvement or recovery of muscular atrophy or fatty infiltration after tendon repair.

Thirty-two consecutive open repairs of a single tendon tear of the rotator cuff were analysed. The supraspinatus tendon was involved in twenty-two patients and the subscapularis tendon in ten patients. All tendons were repaired using an open technique, a modified Mason-Allen suturing technique, and transosseus fixation with non-absorbable suture material knotted over a bone augmentation device.

The generally-accepted treatment for large, displaced fractures of the glenoid associated with traumatic anterior dislocation of the shoulder is operative repair. In this study, 14 consecutive patients with large (> 5 mm), displaced (> 2 mm) anteroinferior glenoid rim fractures were treated non-operatively if post-reduction radiographs showed a centred glenohumeral joint.

After a mean follow-up of 5.6 years (2.8 to 8.4), the mean Constant score and subjective shoulder value were 98% (90% to 100%) and 97% (90% to 100%), respectively. There were no redislocations or subluxations, and the apprehension test was negative. All fragments healed with an average intra-articular step of 3.0 mm (0.5 to 11). No patient had symptoms of osteoarthritis, which was mild in two shoulders and moderate in one.

Traumatic anterior dislocation of the shoulder, associated with a large displaced glenoid rim fracture can be successfully treated non-operatively, providing the glenohumeral joint is concentrically reduced on the anteroposterior radiograph.

We released the infraspinatus tendons of six sheep, allowed retraction of the musculotendinous unit over a period of 40 weeks and then performed a repair. We studied retraction of the musculotendinous unit 35 weeks later using CT, MRI and macroscopic dissection.

The tendon was retracted by a mean of 4.7 cm (3.8 to 5.1) 40 weeks after release and remained at a mean of 4.2 cm (3.3 to 4.7) 35 weeks after the repair. Retraction of the muscle was only a mean of 2.7 cm (2.0 to 3.3) and 1.7 cm (1.1 to 2.2) respectively at these two points. Thus, the musculotendinous junction had shifted distally by a mean of 2.5 cm (2.0 to 2.8) relative to the tendon. Sheep muscle showed an ability to compensate for approximately 60% of the tendon retraction in a hitherto unknown fashion. Such retraction may not be a quantitatively reliable indicator of retraction of the muscle and may overestimate the need for elongation of the musculotendinous unit during repair.

We compared six patients with a mean age of 70 years (49 to 80) with severe bilateral, painful glenohumeral joint destruction who underwent a single-stage bilateral total shoulder replacement, with eight patients of mean age 61 years (22 to 89) who underwent bilateral total shoulder replacement in two stages, at a mean interval of 18 months (6 to 43).

The overall function, pain and strength improved significantly in both groups. The subjective shoulder value, relative Constant score, active external rotation and the strength were improved significantly more in the single-stage group. Active elevation, abduction and overall function improved, significantly more in the single-stage group. Both the total duration of hospitalisation and the time off work per shoulder were substantially shorter in the single-stage group. The overall rate of complication was lower in the single-stage group.

Our findings indicated that single-stage bilateral total shoulder replacement yielded significantly better clinical results with shorter hospitalisation and rehabilitation than staged replacement, and was not associated with any increase in complications.

Introduction: Structural failure of a rotator cuff repair, if associated with pain and severe dysfunction, represents a treatment challenge. Depending on the size of the retear ,the degree of fatty degeneration of the involved muscles, retraction of the musculotendinous unit, as well as age and activity level of the patient, treatment options include re-repair, re-repair with tendon transfer, glenohumeral arthrodesis and inverse total shoulder (Delta) prosthesis. The purpose of this study was to review the outcome of treatment of failed rotator cuff repairs and to compare the results of the four most important types of treatments.

Material and methods: From 1991 till 2002, we retrospectively analysed 80 patients, who underwent revision surgery of the shoulder after failed primary cuff repair. Out of them, 33 had a rerepair, 15 were treated with a delta prosthesis, 17 with a latissimus dorsi-and 15 with a pectoralis major-transfer. Data assessment included pre- and postoperative Constant Score and complication rate. Average follow-up time was 51 months.

Results: After rerepair of the rotator cuff, patients showed a significant gain in subjective shoulder value, rel. Constant Score and reduction of pain(p< 0.05), but range of motion and strength remained unchandged. After additional latissimus-dorsi-or pectoralis major-transfer no significant gain was seen in either subjective shoulder value, nor rel. Constant Score. After Implantation of delta prosthesis, significant improvement was seen in subjective shoulder value, relative Constant score, range of motion and strength (p< 0.05). These improvements were significantly better than in the other groups (p< 0.05). Complication rate was the highest in the delta group.

Conclusion: After failed rotator cuff repair, attempts of rerepair allow good subjective results by reducing pain and maintaining range of motion. Although range of motion is maintained after additional latissimus dorsi-and pectoralis major-transfer, subjective and objective results are not satisfying. After implantation of a delta prosthesis, very good subjective and objective outcome can be predicted, although results are slightly compromised by the high complication rate.

A reversed Delta III total shoulder prosthesis was retrieved post-mortem, eight months after implantation. A significant notch was evident at the inferior pole of the scapular neck which extended beyond the inferior fixation screw. This bone loss was associated with a corresponding, erosive defect of the polyethylene cup. Histological examination revealed a chronic foreign-body reaction in the joint capsule. There were, however, no histological signs of loosening of the glenoid base plate and the stability of the prosthetic articulation was only slightly reduced by the eroded rim of the cup.

We treated 34 consecutive articular fractures of the proximal humerus in 33 patients with good bone quality by open reduction and internal fixation. Anatomical or nearly anatomical reduction was achieved in 30, at a mean follow-up of 63 months (25 to 131), complete or partial avascular necrosis had occurred in 12 cases (35%). Two patients subsequently underwent arthroplasty and six further patients required additional surgery. The 32 patients who did not require arthroplasty obtained a mean Constant score of 78 points or 89% of an age- and gender-matched normal score (66 points or 76% in the presence and 83 points or 96% in the absence of avascular necrosis (p < 0.0005)); 22 were painfree, and seven had mild pain and three moderate pain. The mean active anterior elevation was 156°. Internal fixation of complex fractures of the proximal humerus restored good shoulder function if avascular necrosis did not develop.

Spinal accessory nerve palsy leads to painful disability of the shoulder, carrying an uncertain prognosis. We reviewed the long-term outcome in 16 patients who were treated for pain, weakness of active elevation and asymmetry of the shoulder and the neck due to chronic paralysis of the trapezius muscle, as a result of nerve palsy. Of four patients who were treated conservatively, none regained satisfactory function, although two became pain-free. The other 12 patients were treated operatively with transfer of the levator scapulae to the acromion and the rhomboid muscles to the infraspinatus fossa (the Eden-Lange procedure). At a mean follow-up of 32 years, the clinical outcome of the operatively treated patients was excellent in nine, fair in two, and poor in one patient, as determined by the Constant score. Pain was adequately relieved in 11 and overhead function was restored in nine patients. Pre-operative electromyography had been carried out in four patients. In two, who eventually had a poor outcome, a concomitant long thoracic and dorsal scapular nerve lesion had been present.

The Eden-Lange procedure gives very satisfactory long-term results for the treatment of isolated paralysis of trapezius. In the presence of an additional serratus anterior palsy or weak rhomboid muscles, the procedure is less successful in restoring shoulder function.

Fixation of the glenoid component is critical to the outcome of total shoulder arthroplasty. In an in vitro study, we analysed the effect of surface design and thickness of the cement mantle on the pull-out strength of the polyethylene pegs which are considered essential for fixation of cemented glenoid components. The macrostructure and surface of the pegs and the thickness of the cement mantle were studied in human glenoid bone. The lowest pull-out forces, 20 ± 5 N, were for cylindrical pegs with a smooth surface fixed in the glenoid with a thin cement mantle. The highest values, 425 ± 7 N, were for threaded pegs fixed with a thicker cement mantle. Increasing the diameter of the hole into which the peg is inserted from 5.2 to 6.2 mm thereby increasing the thickness of the cement mantle, improved the mean pull-out force for the pegs tested.

In this prospective, randomised study, we have compared the wear rate of cemented, acetabular polyethylene cups articulating with either a 22 mm or a 32 mm cobalt-chromium head. We evaluated 89 patients who had a total of 484 radiographs. The mean follow-up period was 71.4 months (SD 29.1). All the radiographs were digitised and electronically measured.

The linear wear rate was significantly higher during the first two years and decreased after this period to a constant value. We suggest that this is partly due to a ‘run-in’ process caused by irregularities between surfaces of the cup and head and an initial plastic deformation of the polyethylene. The mean volumetric wear was 120.3 mm³/year for the 32 mm head, which was significantly higher than the 41.5 mm³/year for the 22 mm heads. The mean linear wear rate was not significantly different. We were, however, unable to find radiological signs of osteolysis in the patients who had higher wear rates.

The radiolucent lines and the stability of the components of 66 knee arthroplasties were assessed by six orthopaedic surgeons on conventional anteroposterior and lateral radiographs and on fluoroscopic views which had been taken on the same day. The examiners were blinded as to the patients and clinical results. The interpretation of the radiographs was repeated after five months.

On fluoroscopically-assisted radiographs four of the six examiners identified significantly more radiolucent lines for the femoral component (p < 0.05) and one significantly more for the tibial implant. Five examiners rated more femoral components as radiologically loose on fluoroscopically-assisted radiographs (p = 0.0008 to 0.0154), but none did so for the tibial components. The mean intra- and interobserver kappa values were higher for fluoroscopically-assisted radiographs for both components.

We have shown that fluoroscopically-assisted radiographs allow more reproducible, and therefore reliable, detection of radiolucent lines in total knee arthroplasty. Assessment of the stability of the components is significantly influenced by the radiological technique used. Conventional radiographs are not adequate for evaluation of the stability of total knee arthroplasty and should be replaced by fluoroscopically-assisted films.

We have studied the mechanical properties of several current techniques of tendon-to-bone suture employed in rotator-cuff repair. Non-absorbable braided polyester and absorbable polyglactin and polyglycolic acid sutures best combined ultimate tensile strength and stiffness. Polyglyconate and polydioxanone sutures failed only at high loads, but elongated considerably under moderate loads. We then compared the mechanical properties of nine different techniques of tendon grasping, using 159 normal infraspinatus tendons from sheep. The most commonly used simple stitch was mechanically poor: repairs with two or four such stitches failed at 184 N and 208 N respectively. A new modification of the Mason-Allen suture technique improved the ultimate tensile strength to 359 N for two stitches. Finally, we studied the mechanical properties of several methods of anchorage to bone using typically osteoporotic specimens. Single and even double transosseous sutures and suture anchor fixation both failed at low tensile loads (about 140 N). The use of a 2 mm thick, plate-like augmentation device improved the failure strength to 329 N. The mechanical properties of many current repair techniques are poor and can be greatly improved by using good materials, an improved tendon-grasping suture, and augmentation at the bone attachment.

We report seven cases in which open or closed reduction of a shoulder dislocation associated with a fracture of the humeral neck led to displacement of the neck fracture. Avascular necrosis of the humeral head developed in all six patients with anatomical neck fractures. All five anterior dislocations also had a fracture of the greater tuberosity and both posterior dislocations had a fracture of the lesser tuberosity. The neck fracture had not initially been recognised in three of the seven cases. In five cases attempted shoulder reduction led to complete displacement of the head segment, which was treated by open reduction and minimal internal fixation. In the other two cases, shoulder reduction caused only mild to moderate displacement which was accepted and the fracture was treated conservatively. We conclude that biplane radiography is essential before reduction of a shoulder dislocation. Neck fractures must always be ruled out, especially where there are tuberosity fractures. In our series, careful closed reduction under general anaesthesia with optimal relaxation and fluoroscopic control did not prevent iatrogenic displacement. Prophylactic stabilisation of the neck fracture should be considered before reduction of such a fracture-dislocation. It may be, however, that the prevention of displacement by prophylactic stabilisation does not always prevent late avascular necrosis; we observed this in one case.

We reviewed 25 children who presented consecutively with voluntary (habitual) subluxation of the shoulder. Thirty-six shoulders were involved and symptoms had been present for an average period of 12 years. Eighteen children were managed by 'skillful neglect': all these had become fully active in the profession of their choice and were satisfied with the outcome. Two of them had required shoulder surgery in adult life but only after trauma. Seven children (ten shoulders) had undergone stabilising operations during childhood with the aim of preventing later degenerative arthritis. These patients were also active in their selected professions, but only three (five of the ten shoulders) had good results: two shoulders had recurrent instability, two were painful and one was stiff. None of the shoulders in either group had developed osteoarthritic changes. There was no association with emotional or psychiatric problems. We conclude that voluntary subluxation of the shoulder in children has a favourable prognosis and that there is no indication for surgical intervention during childhood.

Traumatic rupture of the tendon of the subscapularis muscle was documented as an isolated lesion in the shoulders of 16 men. The injury was caused either by forceful hyperextension or external rotation of the adducted arm. The patients complained of anterior shoulder pain and weakness of the arm when it was used above and below the shoulder level. They did not experience shoulder instability. The injured shoulders exhibited increased external rotation and decreased strength of internal rotation. A simple clinical manoeuvre called the 'lift-off test', reliably diagnosed or excluded clinically relevant rupture of the subscapularis tendon. Confirmation of the clinical diagnosis was best achieved by ultrasonography or MRI, but arthrography or CT arthrography were also useful. Surgical exploration confirmed the diagnosis in every case. Repair of the ruptured tendon was technically demanding and required good exposure to identify and protect the axillary nerve.

Five consecutive unstable fractures of the distal third of the clavicle were treated by indirect open reduction and internal fixation using a temporary Bosworth-type screw. Coracoclavicular fixation provided and maintained reduction of the fracture. Healing occurred uneventfully within nine weeks in all cases. The screw was removed under local anaesthesia after healing of the fracture and there were no surgical complications. Shoulder function was restored to the pre-injury level. Temporary coracoclavicular screw fixation appears to be a valuable alternative for the treatment of type II fractures of the distal third of the clavicle.

In the Trillat procedure for recurrent anterior instability of the shoulder the coracoid process is osteotomised and tilted downward to act as a bone block, and a screw is used to fix it and the Bankart lesion to the anterior scapular neck. We reviewed 52 cases after a mean follow-up of 69 months. Results in 73% of shoulders were excellent, 10% were good, 7% fair and 10% poor. Dislocation recurred in 4%, but a positive apprehension sign was present in 10 other shoulders. Some degenerative changes were seen in 62% of shoulders, a complication known to be associated with bone-block procedures. The most important reason for loss of lateral rotation was iatrogenic impingement of the coracoid. This frequent and potentially serious complication can also cause posterior subluxation of the humeral head and osteoarthritis.

Symptomatic impingement of the rotator cuff between the humeral head and the coracoid process has been studied and three varieties recognised: idiopathic, iatrogenic and traumatic. In all three the clinical findings consisted of pain in front of the shoulder, referred to the upper arm and forearm, and especially felt during forward flexion and medial rotation; the pain could be reproduced by medial rotation with the arm in 90 degrees of abduction, or by adduction with the shoulder flexed to 90 degrees. Patients were relieved of their symptoms by restoring adequate subcoracoid clearance.

Anterior and posterior drawer tests of the shoulder are described. Their purpose is to detect anterior and posterior shoulder instability and thereby to eliminate some of the failures of operative treatment. Their value in assessing unidirectional and multidirectional instability both before and after operation is discussed.

Sixty-five knees were subjected to a kinematic analysis using the instant-centre technique in order to determine the effect of deficiency of the anterior cruciate ligament on the biomechanics of active movement in the knee. The instant-centre pathway in acute ruptures of the anterior cruciate ligament was found to have a specific abnormality. This corresponded with a positive pivot-shift sign, but was present even when that sign was not clinically detectable. Primary repair using a transosseous wire suture did not usually abolish the biomechanical abnormality. The data provide a possible explanation for the doubtful prognosis of primary repair of this ligament and encourage clinical and biomechanical evaluation of alternative procedures such as primary augmented repair.