header advert
Results 1 - 9 of 9
Results per page:
Orthopaedic Proceedings
Vol. 96-B, Issue SUPP_19 | Pages 23 - 23
1 Dec 2014
Prins J de Beer M
Full Access

Background:

With the increase in the average age of the population, the incidence of symptomatic rotator cuff tears will also increase. Combined with more access to information via the internet etc., the patient population is more informed of the treatment modalities available and is expecting good reproducible results of their surgeries.

Study:

288 of 426 consecutive open rotator cuff repairs (2010–2012) were examined at 6 month follow up and evaluated for ranges of motion, the integrity of the deltoid and specifically the sonographic integrity of the cuff. All procedures were done in the same manner by the same surgeon (TdB). At the 6 months follow-up all had a sonar of the repaired cuff.

As a second part of the study 319 of 462 consecutive cuff repair patients were phoned and evaluated by means of the ASES score insofar satisfaction with their shoulder as well as functional outcome are concerned.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_29 | Pages 30 - 30
1 Aug 2013
de Beer M
Full Access

Purpose:

The objective of this study was to determine the tensile strength of the different components of the rotator cuff tendons and their relationship to rotator cuff tears.

Method:

The tests were done on a newly designed and built test-bench that performed the tests at a consistent rupture speed. The tests were done on four fresh frozen cadaver shoulders. The capsular and tendinous layers of the rotator cuff were divided leaving them only attached on the humeral side. Separate tensile tests were done on these tendons, after they were divided into 10 mm wide strips before testing. The tendon thickness was also measured.


Orthopaedic Proceedings
Vol. 95-B, Issue SUPP_29 | Pages 78 - 78
1 Aug 2013
de Beer M
Full Access

Purpose:

To determine the insertion of the different layers of the rotator cuff and apply it to rotator cuff tears. Anatomical insertion of the rotator cuff holds the key to a proper anatomical repair.

Method:

A study of the rotator cuff insertion was done in conjunction with MSc student department Anatomy. The rotator cuff consists of a capsular and tendinous layer. They have different mechanical properties. The capsular layer inserts ± 3 mm more medially on the tuberosity and the tendinous layer more laterally. It was shown that the superficial layer extends beyond the greater tuberosity and connects the supra-spinatus tendon to the sub-scapularis tendon via the bicepital groove. This connection was called the “rotator hood”. The “rotator hood” has a mechanically advantageous insertion, is a strong structure with a compressive force on the proximal humerus.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 276 - 276
1 Sep 2005
de Beer M Boon J van der Merwe A Scholtz M Becker P
Full Access

Loosening of the glenoid component after total shoulder arthroplasty is the most common indication for revision surgery and the reason for 40% of postoperative complications. Presupposing that implants would survive better in areas with higher bone mineral density (BMD), we aimed to determine BMD of the cancellous part of the glenoid and the dimensions of its cortical bone.

Using spiral CT scans of the left and right shoulders of 45 men and 25 women with no shoulder pathology, we assessed the BMD of the anterior, middle and posterior subcortical planes of the cancellous part of the glenoid at the superior, middle and inferior levels. The cortical thickness was measured at corresponding sites.

In both sexes, at all three levels we found the posterior plane had the highest BMD and cortical thickness.

These findings indicate that BMD varies between planes and areas of cancellous bone in the glenoid. This may influence the engineering of future implants.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 275 - 276
1 Sep 2005
de Beer M Burger N van Rensburg J
Full Access

The objective of this study was to determine the tensile strength of the different components of rotator cuff tendons.

A test bench that performs tests at consistent rupture speed was used to do separate tensile tests on 10-mm strips of capsular and tendinous layers in four fresh frozen cadaveric shoulders. The layers were left attached only on the humeral side.

The maximum force was comparable but the elongation of the outer part of the tendon was greater, indicating that the capsular part would tear first. On average, a 10-mm strip of capsular layer failed at 170N with elongation of 7 mm, while a 10-mm strip of tendinous layer failed at 230N with elongation of 10 mm.

Using six fresh frozen cadaveric shoulders, we went on to determine the strength of the rotator hood, a thin layer of tendon extending beyond the tuberosity major and connecting the supraspinatus to the subscapularis via the bicipital tunnel. The rotator hood ruptured at a mean force of 70 N.

We concluded that the two layers of the cuff contribute equally to the strength. It is therefore important to repair both layers. The difference in elongation of the tendinous and capsular layers makes the capsular layer more vulnerable to elongation stress. The rotator hood is a strong and important structure, and it is important to repair it.


Orthopaedic Proceedings
Vol. 87-B, Issue SUPP_III | Pages 276 - 276
1 Sep 2005
de Beer M Niksch N
Full Access

After many patients, some of whom were unexpectedly young, had presented with medial migration of the hemi-prosthetic head and erosion of the glenoid, we decided 2 years ago to do preoperative DEXA on all shoulder replacement patients. The aim was first to determine normal bone mineral density (BMD) of the glenoid and secondly to predict which patients would be at risk.

We used the same DEXA method as for the hip. The glenoid was divided into three areas, numbered R1, R2 and R3, and we determined BMD in each of them.

Preliminary studies showed that patients fell into two groups. In one, BMD in the R2 and R3 areas was in the range 0.3 to 0.5. Most often the patients in this group were younger or had acute trauma and the contralateral shoulder was not pathological. BMD in the other group was in the range 0.9 to 1.3. Nearly all patients with OA of the shoulder fell into this group.

In this ongoing study, patients are followed up annually with clinical examination and standard radiographs. Follow-up to date has only been 2 years. So far no medial migration of the hemi-prosthetic head has been noted in patients in the group with BMD between 0.9 to 1.3.


Orthopaedic Proceedings
Vol. 85-B, Issue SUPP_II | Pages 142 - 142
1 Feb 2003
Munting T de Beer M Vrettos B
Full Access

We report on six men and two women (mean age 42.5 years) who had sustained posterior dislocation of the shoulder in motor vehicle accidents (three), falls (two), equestrian accidents (two), cycling accidents (one) and in a fainting spell (one). In four patients, the dislocation was the only injury, but two had humeral shaft fractures, one a humeral neck fracture and the fourth a glenoid and humeral shaft fracture. The mean delay to diagnosis was 14 weeks (2 to 21).

In three patients a medical officer, a general practitioner and a radiologist missed the dislocations, but in five orthopaedic surgeons missed them. Four patients had only anteroposterior radiographs of their shoulder taken, one had anteroposterior and lateral scapular views, and three had anteroposterior and lateral radiographs of the humerus.

Four patients underwent hemi-arthroplasties and the other four open reduction and McLaughlin procedures.

Though rare, posterior dislocations are often missed. Careful examination, especially in the absence of external rotation, can eliminate this. In the presence of a fracture, a dislocation or injury to the joint above and below must be excluded. Anteroposterior and lateral scapular views alone are inadequate in trauma cases and an axillary or modified axillary view should be done. If there is any doubt, CT should be performed.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 77
1 Mar 2002
Olivier C de Beer M Maritz N
Full Access

We evaluated the effectiveness of arthroscopic repair in patients with shoulder instability owing to a bony fragment as part of the Bankart lesion, using spiked Suretacs, sutures and anchors.

Over a two-year period, we followed up 23 of 25 consecutive cases, all with a bony fragment as part of the Bankart lesion. The mean age of patients, all of whom were male, was 21 years (17 to 35). Almost all injuries were sustained playing sports. Patients were clinically evaluated at six weeks and 20 weeks postoperatively and interviewed telephonically.

Full arthroscopic examination was performed in a lateral decubitus position. The affected capsular structures and labrum, with its attached bony fragment, were fully mobilised. The bony fragment was always attached to the capsular structures, with labral ring intact. We used a spiked Suretac anchor to reattach the bony fragment to its original anatomical position, and Mitek anchors and no. 1 Ticron sutures for individual reattachment of the capsule and ligaments. Postoperatively patients were immobilised in a shoulder sling for six weeks. Early restricted active and passive movements were advised. Patients routinely received postoperative physical and biokinetic rehabilitation. The mean follow up period was 16 months (5 to 29). There was no redislocation or subjective instability.

This technique yields excellent results, but because it is technically difficult should be used only by experienced shoulder arthroscopists with thorough knowledge of pathological shoulder anatomy.


Orthopaedic Proceedings
Vol. 84-B, Issue SUPP_I | Pages - 77
1 Mar 2002
de Beer M
Full Access

In shoulder arthroplasty the glenoid component remains a problem. Hemi-arthroplasty requires less theatre time and gives rise to fewer complications. The question is whether the results of hemi-arthroplasty are inferior to those of total shoulder arthroplasty.

We assessed 189 patients who since July 1994 had undergone hemi-arthroplasty or total shoulder arthroplasty, excluding patients who suffered fractures, malunion or nonunion. In 77 patients (41%) the glenoid was replaced. The mean age of patients was 62 years. All humeral and glenoid components were cemented. Preoperative and postoperative assessments included pain (visual analogue scale), muscle strength, range of motion, functional activities and Constant shoulder scores.

At this early stage, total shoulder arthroplasty appears to give slightly better functional results than hemi-arthroplasty. However, there were five (6.5%) complications associated with the glenoid components, including glenoid component fracture, loosening and migration. Hemi-arthroplasty eliminates concerns about glenoid wear and glenoid complications, and we believe total shoulder arthroplasty should be reserved for specific problems.