William Mook

The Incidence of Propionibacterium acnes in Open Shoulder Surgery: A Controlled Diagnostic Study.

BACKGROUND Propionibacterium acnes has arisen as the most common microorganism identified at the time of revision shoulder arthroplasty. There is limited evidence to suggest how frequently false-positive cultures occur. The purpose of this prospective controlled study was to evaluate culture growth from specimens obtained during open shoulder surgery. METHODS Patients undergoing an open deltopectoral approach to the shoulder were prospectively enrolled. Patients with a history of shoulder surgery or any concern for active or previous shoulder infection were excluded. Three pericapsular soft-tissue samples were taken from the shoulder for bacterial culture and were incubated for fourteen days. A sterile sponge was also analyzed in parallel with the tissue cultures. In addition, similar cultures were obtained from patients who had undergone previous shoulder surgery. RESULTS Overall, 20.5% of surgeries (twenty-four of 117) yielded at least one specimen removed for culture that was positive for bacterial growth, and 13.0% of sterile control specimens (seven of fifty-four) had positive culture growth (p = 0.234). P. acnes represented 83.0% of all positive cultures (thirty-nine of forty-seven) at a median incubation time of fourteen days. Among the subjects who had not undergone previous surgery, 17.1% (fourteen of eighty-two) had at least one positive P. acnes culture. Male sex was univariably associated with a greater likelihood of bacterial growth (p < 0.01), and patients who had not undergone previous surgery and had received two or more preoperative corticosteroid injections had a higher likelihood of bacterial growth (p = 0.047). CONCLUSIONS The clinical importance of positive P. acnes cultures from specimens obtained from open shoulder surgery remains uncertain. Male sex and preoperative corticosteroid injections were associated with a higher likelihood of bacterial growth on culture and are risk factors that merit further investigation. Previously reported incidences of positive P. acnes culture results from specimens from primary and revision shoulder arthroplasty may be overestimated because of a substantial level of culture contamination. CLINICAL RELEVANCE P. acnes is isolated via culture at a substantial rate from shoulders undergoing a deltopectoral approach. The clinical importance of culture growth by this low-virulence organism still remains uncertain. Further study is necessary to more specifically characterize culture growth by P. acnes as an infection, commensal presence, or contaminant.

Diagnosis and Management of Periprosthetic Shoulder Infections

➤ The unique bacterial flora of the shoulder present diagnostic and treatment challenges that are distinct from those seen with failed hip and knee arthroplasties.➤ The presentation, diagnosis, and management of suppurative periprosthetic joint infections of the shoulder are similar to those of the hip and the knee.➤ Failed arthroplasties with positive cultures (FAPCs) are poorly performing shoulder reconstructions associated with low-virulence microorganisms that do not evoke a suppurative inflammatory response. Propionibacterium acnes is the predominant bacterium isolated from these cases.➤ With improved surgeon awareness and the addition of longer tissue-culture incubation times, detection of FAPCs has become more common. However, management is hampered by the lack of reliable, timely tests that can determine the presence of less virulent organisms in the preoperative or intraoperative settings.➤ The implications of positive culture results in FAPCs are unclear. Key test characteristics such as the false-positive rate and the prevalence of positive cultures in well-performing shoulders are unknown as there is no useful confirmatory test to validate the culture data and no reliable way to detect the presence of less virulent microorganisms without reoperation.➤ Soft-tissue and osseous deficits are frequently encountered when revising previously infected shoulders. The rate of complications in these scenarios is high, and the outcomes are the least favorable compared with revisions for any other indication.➤ The development of a consensus definition of a periprosthetic shoulder infection is critical to future investigations of these devastating complications.

Allograft Reconstruction of Peroneal Tendons: Operative Technique and Clinical Outcomes

Background: Irreparable peroneal tendon tears are uncommon and require complex surgical decision making. Intercalary segment allograft reconstruction has been previously described as a treatment option; however, there are no reports of the outcomes of this technique in the literature. We describe our technique and present our results using this method. Methods: A retrospective chart review was conducted to identify all patients who underwent intercalary allograft reconstruction of the peroneal tendons. Mechanism of injury, concomitant operative procedures, pertinent radiographic findings, pre- and postoperative physical examination, intercalary graft length, medical history, visual analog scale (VAS) score for pain, Short Form-12 (SF-12) physical health survey, Lower Extremity Functional Score (LEFS), and complications were reviewed. Results: Fourteen patients with peroneal tendon ruptures requiring reconstruction were identified. Mean follow-up was 17 months (range, 7-47 months; median, 12 months). The average length of the intercalary segment reconstructed was 10.8 ± 3.8 cm (range, 6-20 cm). The average postoperative VAS score decreased to 1.0 ± 1.4 (P = .0005). No patient had a higher postoperative pain score than preoperative pain score. Average postoperative eversion strength as categorized by the Medical Research Council grading scale improved to 4.8 ± 0.5 (P = .001). The average SF-12 score improved to 48.8 ± 7.8 (P = .02). The average LEFS improved to 86.4. ± 14.9 (P = .00001). Four patients experienced sensory numbness in the sural nerve distribution, and 2 of these were transient. There were no postoperative wound healing complications, infections, tendon reruptures, or reoperations. No allograft associated complications were encountered. All patients returned to their preinjury activity levels. Conclusion: Allograft reconstruction of the peroneal tendons can improve strength, decrease pain, and yield satisfactory patient-reported outcomes. It can be performed without incurring the deleterious effects associated with tendon transfer procedures. We believe that allograft reconstruction is a safe and useful alternative in the treatment of irreparable peroneal tendon ruptures. Level of Evidence: Level IV, retrospective case series.

Extensile Decompression of the Proximal and Distal Tarsal Tunnel Combined With Partial Plantar Fascia Release in the Treatment of Chronic Plantar Heel Pain

Background. Chronic heel pain that is recalcitrant to nonoperative measures is a rare but disabling condition. There are no reports in the literature of extensile proximal and distal tarsal tunnel release combined with partial plantar fasciotomy in the treatment of chronic heel pain. We present our results. Methods. A retrospective chart review was conducted, and charts were assessed for details of their presenting complaints, physical exam, diagnostic studies, medical history, Visual Analog Scale (VAS) scores for pain, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores, and complications. Results. The mean AOFAS ankle-hindfoot score was 86 ± 12.9 (range = 69-100). Of 15 heels, 10 (67%) had an excellent or good rating at the time of the last follow-up visit. One of 15 (7%) reported a poor outcome. The mean VAS pain score changed from 6.3 ± 3.1 to 1.4 ± 1.8 (P = .001). There were no wound complications or infections. Conclusion. This technique offers another operative option for chronic heel pain that is associated with satisfactory outcomes and rest pain relief. Despite reducing pain at rest in all patients, the majority of patients may be left with mild to moderate residual symptoms with activity that is similar to the outcomes of previously reported procedures. Level of Evidence: Therapeutic, Level IV, Retrospective case series

A Rare Technical Complication Causing ACL Graft Failure: Aberrant Femoral Tunnel Trajectory and Posterolateral Corner Compromise

In order to o reproduce normal joint kinematics of the knee following anterior cruciate ligament (ACL) injury, anatomic reconstruction has been advocated1-6. This can be achieved best by recreating the native ACL footprints. Matching the location of the intra-articular apertures of the femoral and tibial tunnels to the anatomic footprints of the native ACL has been reported to be accomplished most accurately with techniques other than traditional transtibial drilling7-11. In the pediatric population, the trajectory of the femoral tunnel is more heavily scrutinized because of its relationship to the distal femoral physis. However, in adults, clinical evidence is sparse regarding the appropriate tunnel trajectory. Cadaveric studies detailing the anatomic relationships of the femoral tunnel to the structures of the lateral aspect of the knee also have been reported12-16. The proximity of the lateral exit point of the femoral tunnel to critical lateral structures placed with an independent tunnel drilling technique has been shown to be a potential source of iatrogenic injury15. To our knowledge, there are no reports in the literature of injury to the posterolateral corner (PLC) as a result of femoral tunnel placement in ACL reconstruction. We present a case of PLC compromise and ACL graft failure following aberrant femoral tunnel placement in a revision ACL reconstruction. The patient was informed that data concerning the case would be submitted for publication, and he provided consent. A twenty-one-year-old male intercollegiate football player presented after sustaining a knee injury while performing a lateral shuffling drill during an off-season workout. He had been treated by two different orthopaedists and had undergone two surgeries on the affected knee for treatment of ACL insufficiency prior to this most recent injury. Three years prior to presentation, he had ruptured his …