Faculty Bibliography

Achilles tendon pathology is common and affects athletes and nonathletes alike. The cause is multifactorial and controversial, involving biological, anatomical, and mechanical factors. A variety of conditions characterized by Achilles tendon inflammation and/or degeneration can be clinically and histologically differentiated. These include insertional Achilles tendinopathy, retrocalcaneal bursitis, Achilles paratenonitis, Achilles tendinosis, and Achilles paratenonitis with tendinosis. The mainstay of treatment for all of these diagnoses is nonoperative. There is a large body of evidence addressing treatment of acute and chronic Achilles tendon ruptures; however, controversy remains.

BACKGROUND: Injury to subchondral bone is associated with knee pain and osteoarthritis (OA). A percutaneous calcium phosphate injection is a novel approach in which subchondral bone marrow edema lesions are percutaneously injected with calcium phosphate. In theory, calcium phosphate provides structural support while it is gradually replaced by bone. However, little clinical evidence supports the efficacy of percutaneous calcium phosphate injections. QUESTIONS/PURPOSES: We asked: (1) Does percutaneous calcium phosphate injection improve validated patient-reported outcome measures? (2) What proportion of patients experience failure of treatment (defined as a low score on the Tegner Lysholm Knee Scoring Scale)? (3) Is there a relationship between outcome and age, sex, BMI, and preoperative grade of OA? METHODS: Between September 2012 and January 2014, we treated 33 patients with percutaneous calcium phosphate injections. Twenty-five satisfied our study inclusion criteria; of those, three patients were lost to followup and 22 (88%; 13 men, nine women) with a median age of 53.5 years (range, 38-70 years) were available for retrospective chart review and telephone evaluation at a minimum of 6 months (median, 12 months; range, 6-24 months). Our general indications for this procedure were the presence of subchondral bone marrow edema lesions observed on MR images involving weightbearing regions of the knee associated with localized pain on weightbearing and palpation and failure to respond to conservative therapy (> 3 months). Patients with pain secondary to extensive nondegenerative meniscal tears with a flipped displaced component at the level of bone marrow edema lesions, or with mechanical axis deviation greater than 8 degrees were excluded. All patients had Grades III or IV chondral lesions (modified Outerbridge grading system for chondromalacia) overlying MRI-identified subchondral bone marrow edema lesions. Percutaneous calcium phosphate injection was performed on the medial tibial condyle (15 patients), the medial femoral condyle (five patients), and the lateral femoral condyle (two patients). Concomitant partial meniscectomy was performed in 18 patients. Preoperative and postoperative scores from the Knee Injury and Arthritis Outcome Score (KOOS) and the Tegner Lysholm Knee Scoring Scale were analyzed. RESULTS: For patients available for followup, the outcome scores improved after treatment. The KOOS improved from a mean of 39.5 +/- 21.8 to 71.3 +/- 23 (95% CI, 18.6-45.2; p < 0.001) and the Tegner and Lysholm score from 48 +/- 15.1 to 77.5 +/- 20.6 (95% CI, 18.8-40.2; p < 0.001). However, seven of the 22 patients had poor clinical outcomes as assessed by the Tegner Lysholm Knee Scoring Scale, whereas three had fair results, five had good results, and seven had excellent results. The postoperative Tegner Lysholm score was inversely related to the preoperative Kellgren-Lawrence OA grade (R2 = 0.292; F (1.20) = 9.645; p = 0.006). We found no relationship between outcome scores and age, sex, or BMI. CONCLUSIONS: In a study that would have been expected to present a best-case analysis (short-term followup, loss to followup of patients with potentially unsatisfactory results, and use of invasive cotreatments including arthroscopic debridements), we found that percutaneous calcium phosphate injection in patients with symptomatic bone marrow edema lesions of the knee and advanced OA yielded poor results in a concerning proportion of our patients. Based on these results, we advise against the use of percutaneous calcium phosphate injections for patients with advanced osteoarthritic changes. LEVEL OF EVIDENCE: Level IV, therapeutic study.

The management of meniscal pathology continues to evolve as researchers gain a better understanding of the role of the meniscus in normal knee kinematics. Evidence now supports retention or transplantation of meniscal tissue to maintain homeostatic knee mechanisms because the removal of meniscal tissue changes the contact stresses and leads to structural and biomechanical changes in the articular cartilage and the subchondral plate that predisposes the knee to the development of degenerative arthritis. Advances in repair techniques, biologic adjuvants, and progressive tissue-engineering strategies are rapidly adding to the surgeon's armamentarium when dealing with meniscal injury and insufficiency. Early clinical data support many of these advanced techniques. It is helpful to explore meniscal function, pathology, and current treatment modalities, with a focus on meniscal repair and transplantation as well as adjuvants to biologic healing and future directions in this field.

BACKGROUND: The purpose of this study was to evaluate the effect of sling immobilization on driving performance with use of a driving simulator. METHODS: This is a prospective trial with a cohort of 21 healthy volunteers comparing their driving ability with and without sling immobilization on their dominant (driving) extremity. Multiple variables, including number of collisions, off-road excursions, and centerline crossings, were measured with a validated driving simulator. Trials were separated by 2 weeks to control for "adaptations" to the simulator. Statistical significance was found in collisions between sling and no-sling tests. RESULTS: The total number of collisions for trial 1 (no sling) was 36 (mean, 1.7 +/- 1.2) compared with 73 (3.7 +/- 1.6) (P < .01) for trial 2 (sling immobilization). Approximately 70% of participants with upper extremity immobilization were involved in >/=3 collisions; approximately 70% of no-sling participants were involved in