Surgeon variation in glenoid bone reconstruction procedures for shoulder instability

BACKGROUND

Advances in the understanding and management of glenoid bone loss in shoulder instability have led to the development of alternative bony reconstruction techniques to the Latarjet using free bone grafts, but little is known about surgeon adoption of these procedures. This study sought to characterize surgeon variation in the use of glenoid bone reconstruction procedures for shoulder instability and ascertain reasons underlying procedure choice.

METHODS

A 9-question survey was created and distributed to 160 shoulder surgeons members of the PacWest Shoulder and Elbow Society, of whom 65 (41%) responded. The survey asked questions regarding fellowship training, years in practice, surgical volume, preferred methods of glenoid bone reconstruction, and reasons underlying treatment choice.

RESULTS

All surgeons completed a fellowship, with an equal number of sports medicine fellowship-trained (46%) and shoulder and elbow fellowship-trained (46%) physicians. The majority had been in practice for at least 6 years (6-10 years: 25%; >10 years: 59%). Most (78%) performed ≤10 glenoid bony reconstructions per year, and 66% indicated that bony procedures represented <10% of their total annual shoulder instability case volume. The open Latarjet was the preferred primary reconstruction method (69%), followed by open free bone block (FBB) (22%), arthroscopic FBB (8%), and arthroscopic Latarjet (1%). Distal tibia allograft (DTA) was the preferred graft (74%) when performing an FBB procedure, followed by iliac crest autograft (18%), and distal clavicle autograft (6%). The top 5 reasons for preferring Latarjet over FBB were the sling effect (57%), the autologous nature of the graft (37%), its robust clinical evidence (22%), low cost (17%), and availability (11%). The top 5 reasons for choosing an FBB procedure were less anatomic disruption (58%), lower complication rate (21%), restoration of articular cartilage interface (16%), graft versatility (11%), and technical ease (11%). Only 20% of surgeons indicated always performing a bony glenoid reconstruction procedure in the noncontact athlete with less than 20% glenoid bone loss. However, that percentage rose to 62% when considering a contact athlete with the same amount of bone loss.

CONCLUSIONS

Although open Latarjet continues to be the most popular glenoid bony primary reconstruction procedure in shoulder instability, nearly 30% of shoulder surgeons in the western United States have adopted FBB techniques as their preferred treatment modality--with DTA being the most frequently used graft. High-quality comparative clinical effectiveness research is needed to reduce decisional conflict and refine current evidence-based treatment algorithms.

Cycle-dependent matrix remodeling gene expression response in fatigue-loaded rat patellar tendons

Expression profiling of selected matrix remodeling genes was conducted to evaluate differences in molecular response to low-cycle (100) and high-cycle (7,200) sub-failure-fatigue loading of patellar tendons. Using our previously developed in vivo patellar tendon model, tendons were loaded for 100 or 7,200 cycles and expression of selected metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), and collagens were quantified by real-time RT-PCR at 1- and 7-day post-loading. Expression profiles were also obtained from lacerated tendons as an acute injury model. The high-cycle group showed upregulation of TIMP-1, -2, Col3a1, and Col5a1, and downregulation TIMP-4 at both time points, upregulation of MMP-2 at 7-day post-loading and downregulation of MMP-13 and -14 at 1-day post-loading, suggesting overall repair/remodeling. In contrast, the low-cycle loaded group showed upregulation of MMP-2, -3, -13, and Col12a1 at both time points, upregulation of TIMP-1, -2, -3, Col3a1, and integrin β1 and downregulation of integrin α11 at 1-day post-loading and upregulation of Col1a1 at 7-day post-loading, consistent with a hypertrophic (adaptive) pattern. Lacerated tendons showed a typical acute wound response with upregulation of all examined remodeling genes. Differences found in tendon response to high- and low-cycle loading are suggestive of the underlying mechanisms associated with a healthy or damaging response.

Optimal rotation and screw positioning for initial glenosphere baseplate fixation in reverse shoulder arthroplasty

HYPOTHESIS

Critical to the longevity of the reverse shoulder arthroplasty is initial rigid fixation of the glenosphere, determined in part by baseplate screw fixation. We studied screw fixation in baseplates placed in several different orientations.

METHODS

Twelve, lightly-embalmed adult scapulae were implanted using a variable-angle and a fixed-angle baseplate. Baseplates were placed in three rotational positions: 1) 12/6 o'clock, 2) 20 degrees rotation toward the coracoid, and 3) 20 degrees rotation toward the scapular spine.

RESULTS

Superiorly, perpendicular screws for the variable-angle baseplate in the 12 o'clock (39.7 mm) and coracoid (37.7 mm) position and angled screws in the coracoid position (37.5 mm) were found to be the longest. Inferiorly, screws holes made perpendicular to the baseplate yielded the longest screw lengths (37.4 mm), while inferiorly angled screws were shorter, especially in the anterior-inferior glenoid (16.8 mm).

CONCLUSIONS

Overall, baseplate rotation toward the spine yielded the lowest mean screw lengths. Proper initial rotation of the baseplate and screw orientation can optimize initial fixation of the glenosphere in reverse shoulder arthroplasty.

LEVEL OF EVIDENCE

Level IV, Case Series, Treatment Study.

Arthroscopically-assisted treatment of pediatric lateral humeral condyle fractures

BACKGROUND

Pediatric lateral humeral condyle fractures are common injuries. Current treatment recommendations include nonoperative treatment for nondisplaced Milch type 1 fractures; however, truly nondisplaced fractures may be rare. Although closed reduction and percutaneous pinning under arthrographic visualization are most commonly used, anatomical reconstitution of the articular surface may require a lateral Kocher approach. This approach may compromise the vascularity of the distal fragment. To avoid this catastrophic complication while still obtaining anatomical articular surface reduction, we have investigated a new technique in which the lateral condyle fracture is reduced arthroscopically, allowing visualization of the articular surface without the soft tissue dissection required with open approaches. The fracture is then percutaneously pinned and immobilized as previously recommended.

METHODS

Six skeletally immature patients with lateral humeral condyle fractures underwent arthroscopic reduction and percutaneous pinning. The mean age of the patients was 48 months (range, 21-69 months). There were 2 girls and 4 boys. Surgery was performed on 4 left and 2 right elbows. The mean follow-up was 32 weeks (range, 21-44 weeks). Postoperatively, all patients were placed in a long arm cast for 4 weeks. Pins and casts were removed at 4 weeks, and motion was begun. Elbow radiographs were evaluated for fracture healing, articular congruity, malunion, growth disturbance, and presence of avascular necrosis. Range of motion, function, pain, and cosmetic deformity were recorded.

RESULTS

All patients had full active and passive range of motion. There was no difference in range of motion compared with the contralateral side (P < 0.05). All fractures healed radiographically by 4 weeks. There were no cases of nonunion or malunion. No patients developed cubitus varus. One patient developed radiolucency of the capitellum. There were no other complications.

CONCLUSIONS

Arthroscopic reduction and percutaneous fixation of pediatric lateral humeral condyle fractures may offer a safe and effective alternative to open treatment with decreased soft tissue stripping and a possibly decreased risk of malunion or avascular necrosis.

LEVEL OF EVIDENCE

Level IV.

Subscapularis function after total shoulder replacement: results with lesser tuberosity osteotomy

Until recently, little consideration was placed on the integrity of the subscapularis tendon after total shoulder arthroplasty. We have noted that several of our patients exhibited loss of internal rotation strength and subscapularis function after total shoulder arthroplasty utilizing an anatomic soft tissue repair of the subscapularis, both with and without bone tunnels. On the basis of those results, we began removing the subscapularis with a small piece of bone by a lesser tuberosity osteotomy in an attempt to achieve improved subscapularis function through bony healing at the repair site. A retrospective review of 28 patients (30 shoulders) was done of patients who had total shoulder arthroplasty performed between 2001 and 2003. The lesser tuberosity and attached subscapularis were repaired through bone tunnels in all cases. The mean follow-up was 1.1 years. Terminal internal rotation was evaluated by the belly-press examination. Subscapularis function was assessed by the patient's ability to tuck in a shirt behind the back, and 25 of 30 patients (83.3%) reported no difficulty. Belly-press examination results were normal in 18 of 30 patients (60%). Removal of the subscapularis through a lesser tuberosity osteotomy results in reliable restoration of internal rotation strength after total shoulder arthroplasty, as measured by the ability to perform a stomach press and to tuck in a shirt. In comparing these results with our earlier cohort of patients with similar demographics and postoperative rehabilitation that had soft tissue repair, improved results were seen in the group that underwent lesser tuberosity osteotomy.

Rupture of the flexor pollicis longus tendon after volar fixed-angle plating of a distal radius fracture: a case report

We report a case of complete rupture of the flexor pollicis longus tendon 13 months after volar fixed-angle plating of a distal radius fracture. Tendon disruption was associated with a prominent distal volar lip of the plate. The plate was placed at the volar distal lip of the radius, at the location recommended by the manufacturer. Most previous reports of flexor tendon ruptures after volar plating of distal radius fractures have been in improperly placed plates, custom-made plates that were later taken off the market, or in physiologically abnormal tendons. This may be a unique case of flexor pollicis longus rupture with a currently commercially available volar fixed-angle plate, placed at the site recommended by the manufacturer, in a patient without other predisposition to tendon rupture.