Surgical treatment for chondral defects of the knee in competitive running and jumping athletes remains controversial. This study evaluated the performance outcomes of professional basketball players in the National Basketball Association (NBA) who underwent microfracture. Data from 24 professional basketball players from 1997 to 2006 was obtained and analyzed. NBA player efficiency ratings (PER) were calculated for two seasons before and after injury. A control group of 24 players was used for comparison. Study group and control group demographics including age, NBA experience, and minutes per game demonstrated no statistical difference. Mean time to return to an NBA game was 30.0 weeks from the time of surgery. The first season after returning to competition PER and minutes per game decreased by 3.5 (P < 0.01) and 4.9 min (P < 0.05), respectively. The 17 players who continued to play two or more seasons after surgery, the average reduction in their PER and minutes per game was 2.7 (P > 0.05) and 3.0 min (P < 0.26), respectively. A multivariant comparison versus controls demonstrated that power rating during the 2 years after surgery decreased by 3.1 (P < 0.01); while minutes per game decreased by 5.2 (P < 0.001). Twenty-one percent (n = 5 of 24) of the players treated with microfracture did not return to competition in an NBA game. On return to competition player performance and minutes per game are diminished.

Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

Delaying the placement of immediate fixtures by 6-8 weeks after extraction of the natural dentition allows for the elimination of associated infective processes, the achievement of maximum osteoblastic activity that theoretically could help the osseointegration process and complete wound covering that simplifies the placement of grafts or membranes. This study examines the healing associated with 21 fixtures in 14 patients. The fixtures were placed into sockets 6-8 weeks after tooth extraction without the use of barrier membranes or bone substitutes. Measurements were taken immediately prior to fixture placement and 3-6 months later at the abutment placement. Alveolar bone height, the remaining socket depth and diameter and the depth to which a 3.75 mm fixture could be inserted into the socket were measured. After fixture placement the vertical and horizontal measurements from the cover screw to the surrounding alveolar bone and the distance from the cover screw to the CEJ of the adjacent tooth were recorded. All fixtures were integrated at exposure with 1 failure during the follow-up period. The distance from the cover screw to the buccal plate decreased by a mean of 2.17 mm. There was an increase in the mean vertical bone height at all 4 surfaces. When horizontal defects were present, the mean vertical distance decreased from 2.5 +/- 0.37 mm to 0.36 +/- 0.64 mm. When horizontal defects were absent, the mean vertical distance decreased from 3.86 +/- 0.58 mm to 0.48 +/- 0.25 mm. There was also a marked decrease in the horizontal distance between the bone margin and the surface of the fixture from 1.6 +/- 1.73 mm to 0.02 +/- 0.02 mm. These results indicate a strong tendency for the defects to fill-in the horizontal plane and for bone growth to occur in the vertical plane to the height of the cover screw. In conclusion the delayed immediate placement of fixtures has a good short-term prognosis with bone regeneration occurring around the defect without the use of barrier membranes or bone substitutes.

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Background: Anterior cruciate ligament (ACL) graft conditioning protocols to decrease postoperative increases in anterior tibial translation and pivot-shift instability have not been established. Purpose: To determine what ACL graft conditioning protocols should be performed at surgery to decrease postoperative graft elongation after ACL reconstruction. Study Design: Controlled laboratory study. Methods: A 6 degrees of freedom robotic simulator evaluated 3 ACL graft constructs in 7 cadaver knees for a total of 19 graft specimens. Knees were tested before and after ACL sectioning and after ACL graft conditioning protocols before reconstruction. The ACL grafts consisted of a 6-strand semitendinosus-gracilis TightRope, bone–patellar tendon–bone TightRope, and bone–patellar tendon–bone with interference screws. Two graft conditioning protocols were used: (1) graft board tensioning (20 minutes, 80 N) and (2) cyclic conditioning (5°-120° of flexion, 90-N anterior tibial load) after graft reconstruction to determine the number of cycles needed to obtain a steady state with no graft elongation. After conditioning, the grafts were cycled a second time under anterior-posterior loading (100 N, 25° of flexion) and under pivot-shift loading (100 N anterior, 5-N·m internal rotation, 7 N·m valgus) to verify that the ACL flexion-extension conditioning protocol was effective. Results: Graft board tensioning did not produce a steady-state graft. Major increases in anterior tibial translation occurred in the flexion-extension graft-loading protocol at 25° of flexion (mean ± SD: semitendinosus-gracilis TightRope, 3.4 ± 1.1 mm; bone–patellar tendon–bone TightRope, 3.2 ± 1.0 mm; bone–patellar tendon–bone with interference screws, 2.4 ± 1.5 mm). The second method of graft conditioning (40 cycles, 5°-120° of flexion, 90-N anterior load) produced a stable conditioned state for all grafts, as the anterior translations of the anterior-posterior and pivot-shift cycles were statistically equivalent ( P < .05, 1-20 cycles). Conclusion: ACL graft board conditioning protocols are not effective, leading to deleterious ACL graft elongations after reconstruction. A secondary ACL graft conditioning protocol of 40 flexion-extension cycles under 90-N graft loading was required for a well-conditioned graft, preventing further elongation and restoring normal anterior-posterior and pivot-shift translations. Clinical Relevance: There is a combined need for graft board tensioning and robust cyclic ACL graft loading before final graft fixation to restore knee stability.