header advert
Results 21 - 40 of 45
Results per page:
Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_II | Pages 129 - 129
1 May 2011
Hohmann E Tetsworth K
Full Access

Introduction: Malpositioning of the acetabular cup component in total hip arthroplasty can result in increased wear, early nonseptic loosening and is the most common cause of dislocation. Previous research has defined a safe zone with an inclination of 40±10 degrees and anteversion of 15±10 degrees. The purpose of this study was to compare cup placement using imageless navigation to a historical control group using CT based measurements.

Methods: 34 patients receiving a primary hip replacement between June 2005 and December 2006 were enrolled in the study. Alignment of the implant is based on the acquisition of landmarks (ASIS and pubic tubercle) and placement of tracking pins into the ASIS. The target position for all patients was 45 degrees of inclination and 15 degrees of anteversion. The position was determined by postoperative Ct scans of the pelvis. This group was compared to a matched control group.

Results: Descriptive statistics revealed that the demographics of both groups were comparable. Mean cup placement in the navigation group was 46.6±5.9 deg of inclination and 18.8±5.6 deg of anteversion. Mean cup placement in the control group was 48.4±8.85 deg of inclination and 22.33±10.9 deg of anteversion. With navigation 73.7% resp 89.5% of cups were placed within the safe zone for inclination resp. anteversion whereas only 56.2% resp. 50% of cups were placed with freehand technique. Taking both inclination and anteversion into consideration 68.4% of cups were placed in the safe zone with navigation. Only 12.5% were placed for both inclination and anteversion were placed into the safe zone.

Discussion: Computer navigation for total joint arthroplasty, if helpful to the surgeon, has to increase reliability of component placement and show a significant reduction in variation compared to freehand techniques. Our results demonstrate that imageless navigation is a reliable tool which significantly increases precision of acetabular cup placement. Further studies are needed to evaluate and further increase the accuracy of the system.


Orthopaedic Proceedings
Vol. 93-B, Issue SUPP_II | Pages 175 - 175
1 May 2011
Hohmann E Bryant A Tetsworth K Urbaniak M
Full Access

Introduction: Anthropometric anatomical factors may influence mechanical and functional stability of joints. An increased posterior tibial slope places the anterior cruciate ligament at a theroretical biomechanical disadvantage. An increased posterior tibial slope can potentially alter forces during landing tasks by either increasing anterior tibial translation and/or ACL loading. The purpose of this study is to investigate the relationship between posterior tibial slope and anterior cruciate ligament injuries. It is hypothesized that subjects with an ACL injury have an increased posterior tibial slope compared to a normal population.

Methods: Posterior tibial slope in 211 patients (154 male, 57 female) aged 15–49 who underwent anterior cruciate ligament reconstruction was measured using the posterior tibial cortex as reference. A matched control group was used for comparison.

Results: The average posterior tibial slope in the ACLR population was 6.1 degrees while the control group had average values of 5.4 degrees. This finding nearly reached statistical significance (p=0.057). In the male population average values were 5.5 degrees in the ACLR group and 5.9 in the control group. This was not significant (p=0.21). However there was a significant difference (p=0.04) in the female group. ACLR females had higher values 6.5 degrees whereas the control group had average values of 5.2 degrees.

Discussion: Increased posterior tibial slope decreases the inclination of the ACL and potentially decreases vector force during dynamic tasks. It may further result in suboptimal length-tension relationships of agonistic muscles, increases in electromechanical delays and result in lower force development further leading to increased vector forces on the ACL. Posterior tibial slope angles were slightly smaller than with other published studies. However by using the posterior tibial cortex as reference an average of 3 degrees must be added to the measured values. We could not confirm the results of previous studies demonstrating an increased degree of posterior tibial slope in ACL injured patients. However we demonstrated a significant difference in tibial slope in females. Based on our results an increased posterior tibial slope is not a risk factor in males but possibly contributes to ACL injuries in females. Increased posterior tibial slope may be one of the reasons why females have a higher incidence of ACL injuries.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 189 - 189
1 Mar 2010
Hohmann E Tay M Tetsworth K Bryant A
Full Access

Anterior cruciate ligament reconstruction has become a standard procedure with a documented good and excellent outcome of 70–90%. Important variables of outcome after surgery consist of objective and subjective variables. It is important to examine the relationship between commonly used knee rating systems and functional tests to assess whether there is a correlation between rating systems and functional performance. The purpose of this study was to determine if a correlation exists between four commonly used knee rating systems (Lysholm, Tegner, IKDC, Noyes) and commonly performed dunctional tests: single and timed hop, vertical jump and isometric, isokinetic and eccentric muscle strength.

44 consecutive patients (31 males and 13 females) were selected (mean age 27.9 years). All subjects were tested prior and 12 month following anterior cruciate ligament reconstruction. The subjects completed the above knee rating scores. The patients were then evaluated performing the following tests: single leg hop for distance, timed hop and vertical jump. Muscle strength was assessed using a Biodex dynamometer. Isometric strength was examined at 30 and 60 degrees of flex-ion. Isokinetic testing (concentric and eccentric) was performed at 120 and 180 degrees/sec. Their results of functional testing were expressed as percentage of the contralateral non involved limb.

A positive correlation was found between single leg hop, Lysholm (r=0.53, p< 0.05). IKDC (r=0.30, p< 00002) and Noyes score (r=0.45, p< 0.01). A positive correlation was found between vertical jump, Lysholm (r=0.21, p< 0002), IKDC (r=0.31, p< 0.0001) and Noyes score (r=0.31, p< 0.0001). There was no correlation between timed hop and knee scores. A negative correlation (r=0.25–0.46) was noted between eccentric peak extension torque at 120 degrees/sec and 180 degrees/sec (r=0.230.26). However it only reached significance (p< 0.04) between IKDC and eccentric torque at 120 degrees/sec and 180 degrees/sec (p< 0.01). In addition there was a moderate negative correlation (r=0.26, p< 0.0004)) between Lysholm score and eccentric peak torque at 180 degrees/sec. No correlations were found for isokinetic and isometric torque for the knee flexors.

Knee rating systems seem to reflect functional capabilities and subjective satisfaction of patients prior and post ACL reconstruction. Isokinetic strength does not seem to be an important predictor of knee function.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 183 - 183
1 Mar 2010
Hohmann E Tay M Tetsworth K Bryant A
Full Access

Malpositioning of the acetabular cup component in total hip arthroplasty can result in increased wear, early nonseptic loosening and is the most common cause of dislocation. Previous research has defined a safe zone with an inclination of 40±10 degrees and anteversion of 15±10 degrees. The purpose of this study was to using CT based measurements.

32 patients receiving a primary hip replacement between June 2005 and December 2006 were enrolled in the study. Alignment of the implant is based on the acquisition of landmarks (ASIS and pubic tubercle) and placement of tracking pins into the ASIS. The target position for all patients was 45 degrees of inclination and 15 degrees of anteversion. The position was determined by postoperative Ct scans of the pelvis. This group was compared to a historical control group.

Descriptive statistics revealed that the demographics of both groups were comparable. Mean cup placement in the navigation group was 46.6±5.9 deg of inclination and 18.8±5.6 deg of anteversion. Mean cup placement in the control group was 45.8±9.5 deg of inclination and 27.3±15.0 deg of anteversion. With navigation 73.7% resp 89.5% of cups were placed within the safe zone for inclination resp. anteversion whereas only 60.9% resp. 39% of cups were placed with freehand technqie. Taking both inclination and anteversion into consideration 68.4% of cups were placed in the safe zone with navigation. Only 25.7% were placed for both inclination and anteversion were placed into the safe zone.

Computer navigation for total joint arthroplasty, if helpful to the surgeon, has to increase reliability of component placement and show a significant reduction in variation compared to freehand techniques. Our results demonstrate that imageless navigation is a reliable tool which significantly increases precision of acetabular cup placement. Further studies are needed to evaluate and further increase the accuracy of the system


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 194 - 195
1 Mar 2010
Hohmann E Imhoff A
Full Access

Large osteochondral defects of the femoral condyle still pose a difficult problem to treat. A variety of options is available but most of result in replacement with inferior fibrous or hyaline-like cartilage in the load-bearing zone of the knee joint. We present the five year results of Mega-OATS. This technique utilizes the posterior femoral condyle for coverage of osteochondral defects and is called Mega-OATS.

From July 1999, 33 patients of mean age 34.3 years (15–59) were treated with MEGA-OATS. Fifteen patients additionally underwent high tibial osteotomy and two bone grafting using bone harvested from the proximal tibia. The average defect size was 6.2±1.8 cm2. The mean follow up was 66.4±13.2 months. The technique calls for excision of the posterior femoral condyle which is placed in a specially designed work station.

The Lysholm score increased post-operatively from 49.0±19.4 to 88.5±14.9 12 months post surgery to 85.5±16.0 five years post surgery. Three months post-operatively, patients attained a full range of motion and became fully weight-bearing. There was no difference in patients undergoing combined surgery with high tibial osteotomy and patients undergoing Mega OATS as a single procedure after five years. No post-operative meniscal lesions of the posterior horn have been observed.

Mega-OATS achieves a congruent reconstruction of the articular surface in the load bearing zone of the femoral condyle. We consider it a good alternative and salvage procedure in the treatment of large osteochondral defects of the femoral condyle.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 189 - 189
1 Mar 2010
Hohmann E Tay M Tetsworth K Bryant A Tay M
Full Access

Anterior cruciate ligament reconstruction has become a standard procedure with a documented good and excellent outcome of 70–90%. It has been demonstrated by previous research that all patients following surgery demonstrate a strength deficit of almost 20%. However it is not known whether these strength deficits have an influence on postoperative functionality.

52 consecutive patients (38 males and 14 females) were selected (mean age 27.9 years). All subjects were tested prior and 12 month following anterior cruciate ligament reconstruction. Muscle strength was assessed using a Biodex dynamometer. Isometric strength was examined at 30 and 60 degrees of flexion. Isokinetic testing was performed at 180 degrees/sec and peak torque and symmetry indices were analysed.

No correlations were found between the Cinncinnati Score and isokinetic peak torque for extension. A moderate significant (p=0.001–0.007) correlation (r=0.200.45) was found for peak flexion torque in ACL reconstructed patients. In ACL deficient patients symmetry indices (r=0.36–0.43, p=0.001–0.004) were moderately related to functionality for both flexion and extension.

Quadriceps muscle strength does not seem to be an important predictor of knee function after ACL reconstruction. Flexors seem to be important to protect the graft from overload. In ACLD knees functionality is related to high symmetry indices suggesting similar strength is necessary to perceive knee function as near normal. This is possibly a normal neuromuscular adaptation caused by contralateral quadriceps avoidance.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 194 - 194
1 Mar 2010
Coyle C Tay M Tetsworth K Bryant A Hohmann E
Full Access

Gait analysis is an important tool to measure function following total knee replacement. It is currently unknown whether there is a correlation between subjective and objective outcome variables. The purpose of this study was to analyse relationships between subjective outcome scores and kinematic and kinetic data.

25 consecutive patients (15 males, 10 females) were selected (mean age 68 years, BMI 31.8). All subjects were tested a minimum of 24 months following total knee replacement. SF12, Oxford knee score, knee society and KOOS scores were collected. Muscle strength was assessed using a Biodex dynamometer and symmetry indices were analysed. A timed up and go test and KT2000 measurements were performed.

Strong correlations (r=0.52–0.74) were found between scoring systems (SF 12, Oxford knee score, knee society score, KOOS score) and the timed up and go test. Moderate correlations (r=0.27–0.35) were found between knee scores and KT2000 measurements. Only weak correlations (r=0.09–0.12) were found between knee scores and strength. None of the correlations reached statistical significance. Post hoc contrasts demonstrated adequate power (0.95) of the study.

The finding of this study suggests that outcome scores and objective and functional tests following total knee arthroplasty measure different variables of outcome. Whilst objective tests and gait analysis provide an understanding of joint mechanics after surgery and can be used to calculate resultant forces and moments, patient perceived outcomes have no Significant correlation to knee biomechanics. This may be related to factors such as pain relief, improved quality of life and the ability to perform activities of daily life. In contrast modern implants may provide a satisfactory outcome resulting in high patient satisfaction. The results of this study underline the importance of using subjective patient outcome measures to follow up total knee replacement patients.


Orthopaedic Proceedings
Vol. 92-B, Issue SUPP_I | Pages 214 - 214
1 Mar 2010
Hohmann E Tay M Tetsworth K Bryant A
Full Access

Non-operative treatment of lateral clavicle fractures presents a difficult problem. A high incidence of non-union, residual pain and shoulder girdle instability has been reported. A variety of fixation techniques have been described but the complication rates of these procedures can be high. This retrospective review describes the use of distal radius locking plates for fixation of lateral unstable clavicle fractures.

From January 2006 until December 2007 23 patients (17 males, 5 females; mean age 31 yrs (12–70) presented to our service. 2 patients sustained type 1, 16 patients type 2, 2 patients type 4 and 3 patients type 5 fractures (Neer classification). Patients were reviewed clinically, radiographically and with Constant score assessment.

Union was acchieved at a mean follow up of 7.2 weeks. The mean Constant score at 6 months was 84, the mean DASH score 27.7. The following complications were seen during the follow-up period: 1 superficial infection settling with oral antibiotics and 1 non-union in a type 5 fracture requiring bone grafting.

Clavicle fractures of the lateral aspect are controversial. The mechanism of injury often results in ruptures of the adjacent coracoclavicular ligaments and create instability and increased motion between the proximal and distal fragment. The result of this series of cases are encouraging and we recommend the use of distal radius locking plates to treat unstable lateral clavicle fractures. However a larger study is needed to further evaluate mid- and long-term shoulder function.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 349 - 349
1 Sep 2005
Hohmann E Bryant A Eiling E Peterson W Murphy A
Full Access

Introduction and Aims: Hormonal factors are one plausible explanation for differences in musculotendinous stiffness (MTS) and knee laxity between men and women, and the resulting higher risk for ACL injury in women. This study examined MTS and ACL laxity over the course of the menstrual cycle in women and investigated the interaction of warm-up.

Method: Eight female netball players aged between 16–18 years (mean = 16.3 ± 0.8 years) participated in this study. None of the participants were using oral contraceptives and all demonstrated regular menstrual cycles. Venous blood samples and MTS data were collected each week over the 28-day menstrual cycle. MTS was assessed prior to, and following a standardised warm-up consisting of light cycling and jumping. ACL laxity was determined at the beginning of each test session using the KT2000™ knee arthrometer (MEDmetric Corporation, San Diego, USA).

Results: Repeated measures ANOVA results revealed significant (p < 0.05) main effects of warm-up and test session on MTS. For the effect of warm-up, MTS was found to significantly decrease by 4.2% following the warm-up intervention, indicating that relatively low levels of activity can acutely alter the viscoelastic properties of muscle. Post hoc contrasts for test session revealed that MTS was significantly lower at week three (corresponding to the ovulatory phase), in contrast to weeks one and two (7% and 4.5% decrease, respectively). For ACL laxity, repeated measures ANOVA revealed no significant (p < 0.05) differences at 30 lb anterior force across the menstrual cycle. The results did however demonstrate a trend towards increased ACL laxity during ovulation (week three) when the lower limb musculature was most compliant.

Conclusion: While there were no significant differences in static ACL laxity, reduced MTS is one of the main causes of prolonged electromechanical delay (EMD) and has particular relevance for ACL injury. In conclusion, females are at greater risk of incurring an ACL injury during ovulation when oestrogen levels are highest.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 309 - 309
1 Sep 2005
Hohmann E Radziekowski J Wiesniewski T
Full Access

Introduction and Aims: Primary wound closure in open tibial fractures has not been recommended. Studies suggest that infections are not caused by the initial contamination but the organisms acquired in the hospital. Primary wound closure after adequate wound care and fracture stabilisation should be a safe concept.

Method: We analysed 95 patients with open tibial fractures Gustilo-Anderson Type 1-3a treated with primary fracture stabilisation and delayed wound closure (group I) and primary fracture stabilisation and primary wound closure (group II). In group I, 46 patients (38 males, eight females) with a mean age of 30.2 years (range 16–56) were included. In group II, 49 patients (36 males, 13 females) with a mean age of 33.4 (range 18–69) were included. The mean follow-up in group I was 11.5 (range 9–18) and 11.7 (range 8–16) months.

Results: The mean operating time in group I was 96 (range 45–180) minutes, in group II, 101 (range 40–170) minutes. The hospital stay in group I was 8.6 (range 3–20) days and in group II, 15.4 (range 4–52) days. One infectious case in group I was seen (2%) and two cases in group II (4.3%) were found. On further analysis, one case in group II, in our opinion, should not have been treated with primary fixation and wound closure. He only had three doses of a first generation cephalosporin and was operated 20 hours after admission to hospital. The corrected infection rate in group II should therefore should be calculated without that case and then is 2.1%.

Conclusions: Our results support recent findings that primary wound closure after thorough debridement in Grade I and II open fractures does not increase the infection rate in comparison to the standard treatment. It shortens hospital stay and is cost-effective treatment. We conclude that primary wound closure is safe.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 349 - 350
1 Sep 2005
Hohmann E Imhoff A Woertler K
Full Access

Introduction and Aims: The possible deleterious effects of long distance running remain controversial. The repetitive loading could potentially predispose to the subsequent development of osteoarthritis. The purpose of this study is to investigate whether external impact loading in marathon runners creates internal stresses on bone and cartilage that are demonstrable on MR images.

Method: Six recreational, two semi-professional runners and seven beginners underwent magnetic resonance (MR) imaging of the hip and knee before and after a marathon run using coronal body phased-arrayed coil and the following pulse sequences: a coronal T1 weighted spin echo sequence and STIR sequences. To be included in the study, the runners had to successfully finish a previous race in less than 4.5 hours. The following exclusion included surgery for overuse injuries in the prior 48 months, and symptoms of overuse in the six months preceding the race.

Results: The pre- and post-run scans failed to demonstrate marrow oedema, periosteal stress reactions or joint effusions in seven runners. One patient who underwent a reconstruction of his anterior cruciate ligament 18 months ago demonstrated a small effusion in the reconstructed knee before and after the race. Six of the beginners demonstrated minimal effusions in the hip and knee joints. However no bone oedema was seen in any of the beginners.

Conclusions: Our results suggest that the high impact forces in long distance running are well tolerated and subsequently not demonstrated on MR images in experienced runners. Beginners do compensate the impact stresses to a certain extend and it is postulated that long distance runners undergo a natural selection process.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_I | Pages 25 - 25
1 Mar 2005
Hohmann E Imhoff A
Full Access

High tibial osteotomies are commonly performed for varus/valgus malalignment of the knee. In the past we have been well aware that a high tibial osteotomy corrects the coronal plane but we did not consider changes of the tibial slope. Altering the slope has an impact on the in situ forces of the cruciate ligaments and influences the stability of the knee. The purpose of this study was to investigate the amount of alteration of the tibial slope by a closed wedge osteotomy.

From January 2001 to September 2001 we reviewed retrospectively all Xrays of patients that underwent a high tibial osteotomy or were admitted for removal of hardware. 80 patients were included. 67 patients could be followed up.

The slope on the preoperative xrays was 6,1 degrees (0–12). A closed wedge osteotomy decreased the slope by a mean of 4,88 degrees. A high tibial osteotomy of six degrees in the coronal plane decreased the slope by 4.29 degrees, a HTO of eight degrees decreased the slope by 7 degrees, a HTO of ten degrees by altered the slope by 4.75 and of twelve degrees by decreased the slope by 6.5 degrees.

A closed wedge osteotomy decreases the tibial slope. It is the preferred technique when a combined procedure (HTO and ACL reconstruction) is planned. There is no correlation between the degree of correction of the coronal plane by a closed wedge high tibial osteotomy and changes of the tibial slope.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_I | Pages 26 - 26
1 Mar 2005
Hohmann E Schoettle R Imhoff A
Full Access

Osteochondral autologous transplantation (OATS) is a new technique for the treatment of osteochondral defects.

In a prospective study between April 1996 und May 2001 we used the OATS technique to treat 201 patients (125 male, 76 female) with a mean osteochondral defect of 3,3 cm2. The defect was in the medial femoral condyle in 96 cases, the lateral femoral condyle in 16, the patella in 22, the trochlea in seven, the tibial plateau in one, the talus in 48, the tibial plafond in two and capitellum in four. There were 17 other locations. The procedure was performed either open or arthroscopically. A mean of 2,2 cylinders was transplanted.

The Lysholm score in the lower limbs increased from a preoperative mean of 58,3 (20 to77) to a mean of 90,2 (70 to 100). Treatment by OATS alone increased the score from 65,2 to 91,6. With additional ACL/PCL reconstruction, the score increased from 49,9 to 82,6. The combination of OATS, HTO, ACL/PCL reconstruction increased the Lysholm score from 55,5 to 85,5. Ten per cent of patients complained of pain at the donor site in the lateral femoral condyle. There were no complications related to OATS performed in the upper limbs, and control MRI three months postoperatively showed incorporation of all cylinders.

The results are encouraging, and give rise, to the hope that this cost-effective and safe treatment for limited osteochondral defects may delay or even prevent the onset of osteoarthritis.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_I | Pages 24 - 24
1 Mar 2005
Hohmann E Schmid A
Full Access

Traumatic shoulder dislocations at young age result in a significant re-dislocation rate and lead to chronic instability. Conservative treatment fails in 25–96% of cases especially in young active patients. The accepted standard treatment is the classical open Bankart repair which almost always results in loss of motion. The development of new techniques and devices has lead to an increase in arthroscopic techniques for shoulder stabilisations.

Between September 1996 and October 2000 262 arthroscopic shoulder stabilisations were performed by the senior author: 159 cases FASTak® titanium anchors, 26 Panalok® anchors and 57 cases Suretac® anchors were used. Minimum follow up was 12 months with a mean follow up of 24.9 months (12–50). Rowe score and a visual analogue scale was used to measure patient satisfaction.

The Rowe score increased to 83,1 +/− 20,9. The visual analogue score demonstrated overall patient satisfaction. Complications included redislocations(4.7%) sub-luxations (6.3%) and ongoing instability (6.3%). Return to sports occurred in 89.1% of patients with 68.4% being able to return to their previous sports activity level.

This study demonstrates that arthroscopic shoulder stabilisation is comparable to the gold standard open Bankart repair. It is associated with a high patient satisfaction, lower morbidity, faster return to the previous activity level, better range of motion and less postoperative pain. The disadvantage of the technique is a long learning curve and the potentially longer operating times.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_I | Pages 24 - 24
1 Mar 2005
Hohmann E Schmid A Martinek V Imhoff A
Full Access

Posttraumatic shoulder instability is a common problem in the field of sports medicine. Especially overhead athletes need intact stabilisers to meet the functional requirements. Open procedures often result in limitations of movement postoperatively. Arthroscopic techniques offer potential advantages such as better range of motion and shorter rehabilitation times.

Between September 1996 and October 2000 159 arthroscopic shoulder stabilisations were performed with FASTak® anchors. The mean follow up was 24.9 months (12–50). Rowe score and a visual analogue scale were used to measure patient satisfaction. 72 patients (m=57, f=15)with a mean age of 27.6 years (17–65) were included and clinically examined.

The Rowe score increased to 83.1 after primary stabilisation and 68.1 after revision procedures. The visual analogue score demonstrated overall patient satisfaction. 89.1% (n=64) of the patients could return to sports with 68,4% (n=49) being able to return to their previous sports activity level. Overhead athletes returned to sports in 89.4% of cases and 63.3% to their pre-injury level. In the non-overhead athletes 86% returned to sports with 60% to their pre-injury level.

This study demonstrates that arthroscopic shoulder stabilisation with FASTak® anchors may be offered to the athlete regardless of the sports activity. It allows return to sports in a high percentage and does offer the potential advantages of a faster return to the previous activity level, better range of motion and less postoperative pain. Disadvantages of the technique is a long learning curve and should therefore only be performed by dedicated and experienced shoulder surgeons.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 481 - 481
1 Apr 2004
Hohmann E Schoettle P Imhoff A
Full Access

Introduction Osteochondral autologous transplantation (OATS) is a technique to treat hyaline cartilage injuries in different joints. It delivers high quality hyaline cartilage to the defect.

Methods In a prospective study we used the OATS technique in 201 patients (125 male, 76 female). The mean defect size was 3.3 sq cm. The medial femoral condyle was treated in 96 cases, the lateral femoral condyle in 16, the patella in 22, the trochlea in seven, the tibial plateau in one, the talus in 48, the tibial plafond in two and the capitellum in four. There were 17 other locations. The procedure was performed either open or arthroscopically. A mean of 2.2 cylinders were implanted. Mal-alignment was corrected in 20 cases with an osteotomy and instability of the knee by anterior (ACL) or posterior (PCL) reconstruction. Five patients required reconstruction of both the ACL and PCL.

Results The Lysholm score increased from 58.3 (20 to 77) to a mean of 90.2 (70 to 100) in the lower extremity. Treatment by OATS alone increased the score from 65.2 to 91.6. With additional ACL/PCL reconstruction, the score increased from 49.9 to 82.6. The combination of OATS, HTO and ACL/PCL reconstruction increased the Lysholm score from 55.5 to 85.5. Post-operative MR imaging with intravenous contrast showed incorporation of all but one cylinder. Complications included one case of arthrofibrosis and sinking of one cylinder. One patient developed regional pain syndrome and three had pain at the malleolar osteotomy site resolved by screw removal. Ten percent of the patients developed pain at the donor site.

Conclusions The results are encouraging. It is a cost effective and safe treatment.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 472 - 472
1 Apr 2004
Hohmann E Imhoff A
Full Access

Introduction High tibial osteotomies (HTO) are commonly performed for either varus or valgus malalignment of the knee. In the past we have been well aware that HTO corrects the coronal plane of the knee, but we did not consider changes of the tibial slope in the sagittal plane when planning or evaluating osteotomies. Because the tibia is a three-dimensional structure with a triangular shape, osteotomy may result in changes in both the coronal plane and the sagittal plane. Altering the tibial slope has an impact on the in situ forces of the cruciate ligaments and may influence the stability of the knee. The purpose of this study is to investigate any possible alteration of the tibial slope introduced by HTO.

Methods This study was conducted as a retrospective radiographic review of a consecutive series of patients. Between January and September 2001 a total of 80 patients underwent either HTO or the removal of hardware from a prior HTO. The radiographs of 67 of these patients were suitable for review. There were 41 males with an average age of 36.6 years (17 to 67). There were 26 females with an average age of 39.4 years (19 to 62). Routine radiographs of the knee were obtained using standard methods, and these were assessed by comparison to corresponding preoperative studies.

Results The posterior slope on pre-operative radiographs averaged 6.1° (0 to 12). HTO using a closing wedge technique was found to decrease this posterior slope by a mean of 4.9°. The change in the posterior slope was not found to correlate directly with the magnitude of the correction in the coronal plane. HTO of six degrees in the coronal plane decreased the posterior slope by 4.3° degrees, HTO of eight degrees decreased the posterior slope by seven degrees, HTO of 10° altered the slope by 4.8° degrees, and HTO of 12° degrees decreased the posterior slope by 6.5°.

Conclusions HTO by a closing wedge technique for sagittal plane correction often distorts alignment in the coronal plane as well, resulting in a decrease in the normal posterior tibial slope. We found no direct correlation between the degree of correction of the coronal plane and alteration of the tibial slope. Decreasing this slope potentially decreases in situ forces acting on the ACL while simultaneously increasing forces acting on the PCL. This may have advantages when managing combined cases with both malalignment and instability. The closing wedge technique is our preferred method when a combined procedure (HTO and ACL reconstruction) is planned.

In relation to the conduct of this study, one or more of the authors has received, or is likely to receive direct material benefits.


Orthopaedic Proceedings
Vol. 86-B, Issue SUPP_IV | Pages 488 - 488
1 Apr 2004
Hohmann E Schmid A Martinek V Imhoff A
Full Access

Introduction Traumatic shoulder dislocations at a young age result in a significant re-dislocation rates and lead to chronic instability. Conservative treatment fails in 25% to 96% of cases especially in young active patients. The accepted standard treatment is the classical open Bankart repair. Re-dislocation rate could be decreased to 3.5% to 14.9% but almost always results in loss of motion. The development of new techniques and devices has lead to an increase in arthroscopic techniques for shoulder stabilisations.

Methods Between September 1996 and October 2000, 262 arthroscopic shoulder stabilisations were performed by one surgeon (ABI). For the refixation of the injured labrum suture anchors were used. In 159 cases FASTak (Arthrex) titanium anchors, in 26 cases Panalok (Mitek) and in 57 cases Suretac (Smith and Nephew) were used. The minimum follow-up was 12 months with a mean follow-up of 24.9 months (12 to 50). Exclusion criteria were SLAP and HAGL lesions, glenoid fractures, the inverted pear sign and hooked or posterior dislocations. Rowe score and a visual analogue scale were used to measure patient satisfaction.

Results The Rowe score increased to 83.1 +/− 20.9. The visual analogoue score demonstrated overall patient satisfaction. The redislocation rate was five percent, three percent having a history of adequate trauma. Complaints of subluxations and ongoing instability occured in six percent. Eighty-nine percent of the patients could return to sports with 68% being able to return to their previous sports level.

Conclusions This study demonstrates that arthroscopic shoulder stabilisation is comparable to the golden standard of open Bankart repair.


Orthopaedic Proceedings
Vol. 85-B, Issue SUPP_III | Pages 207 - 208
1 Mar 2003
Hohmann E Imhoff A
Full Access

It is suggested that there is a link between arch type of the foot and overuse injuries. The use of individual selected running shoes can reduce running injuries substantially. To select the correct shoe the runner needs to have appropriate knowledge of his own foot anatomy and biomechanics. A questionnaire was used to investigate the knowledge of the runner about his arch height and biomechanics of running. Clinical examination was performed by 5 orthopaedic surgeons and experienced orthopaedic technicians. Weight-bearing podograms were used to further define the deformity.

We examined 92 volunteers with a mean age of 35.4 (12–63) years, a mean size of 176 cm (154–195) with a mean body weight of 70.38 kg (45–95). Eighteen out of 47 runners with a flatfoot deformity identified their deformity correctly. Twenty five out of 43 volunteers with a normal arch were correct in assessing their foot. Two runners with a cavus foot were correct in identifying their foot. Only 4 out of 38 runners that diagnosed themselves as being pronators have been found to be pronators. Four runners with a self-diagnosed non-pro-nating foot were classified as being pronators. Three runners that could not classify themselves were diagnosed as pronators.

This study demonstrates the poor knowledge of foot deformities in the running community.


Orthopaedic Proceedings
Vol. 85-B, Issue SUPP_III | Pages 207 - 207
1 Mar 2003
Hohmann E Brucker P Imhoff A
Full Access

Large osteochondral defects are difficult to treat, but several treatment options are available. The posterior condyle transfer salvage technique described by Wagner in 1964 and Imhoff in 1990 has been developed further and is now used for coverage of large osteochondral defects in the load-bearing zone. The new technique is called MEGA-OATS.

From July 1999, 25 patients of mean age 33.3 years (17 to 60) were treated with MEGA-OATS. Thirteen patients additionally underwent high tibial osteotomy and two bone grafting, using bone harvested from the proximal tibia. The mean follow up was 17.8 months. The technique calls for excision of the posterior femoral condyle which is placed in a specially designed work station. A MEGA-OATS cylinder of diameter 20 mm to 35 mm is prepared and, using the press-fit technique, grafted into the prepared defect zone. The Lysholm score increased postoperatively from 66.33 (49 to 71) to 87.8 (72 to 97). Three months postoperatively control MRI showed incorporation of all cylinders. Between six and 12 weeks postoperatively patients attained a full range of motion and became fully weight-bearing. To date one superficial infection resolving on oral antibiotics and two cases of arthrofibrosis four months postoperatively that required arthroscopic release were seen. No postoperative meniscal lesions of the posterior horn have been observed.

MEGA-OATS achieves a congruent reconstruction of the articular surface in the load-bearing zone of the femoral condyle. We consider it a good alternative in the treatment of large osteochondral defects of the femoral condyle in young patients.