Katsuhiko Kitaoka

Massive autoclaved allografts and autografts for limb salvage surgery. A 1-8 year follow-up of 23 patients.

We performed 23 reconstructions with bone grafts autoclaved at 135 degrees C for 10 minutes for extensive bone defects after tumor resection. In 15 cases, the resected specimens were autoclaved and used as autografts. In 7 cases, allografts obtained from amputated extremities or cadavers were autoclaved and immediately stored at -80 degrees C prior to their use. A combination of the two was used in 1 case. The grafts were used in combination with prostheses or other forms of internal fixation. The mean follow-up was 49 (14-98) months. Incorporation of the hostgraft junction was observed radiographically after a mean of 11 (6-17) months in all cases. No recurrence due to the autoclaved bone was observed. However, 10 patients suffered complications, including infection, bone resorption, fracture and loosening of the prosthesis. In terms of Mankins evaluation of bone grafts, 12 patients were evaluated as good or excellent. We conclude that despite the complications, autoclaved autografts and allografts are viable options for reconstruction in many countries because of the difficulty of obtaining large quantities of fresh frozen allografts.

Outcomes and failure factors in surgical treatment for osteochondritis dissecans of the capitellum

Background: Osteochondritis dissecans (OCD) of the capitellum is an intra-articular lesion and one of the leading causes of permanent elbow disability. The treatment of advanced capitellar OCD remains challenging because of the limited potential of the articular cartilage for self-repair. The purpose of this study was to investigate the outcome of surgical treatment for OCD of the capitellum. Methods: From 2000 to 2010, 32 male patients who had advanced lesions of capitellar OCD were treated operatively. The mean age of the patients was 14.4 years at the time of surgery. Twenty-nine patients played baseball and 3 played other sports. The lesions were of the centralized type in 9 patients, the lateral type in 4 patients, and the widespread type in 19 patients. For the surgical procedure, osteochondral peg fixation was selected for 13 patients and osteochondral autograft transplantation for 19 patients. Clinical outcome was measured with the elbow rating system including range of motion, and the number of patients who returned to active sports participation within 1 year after surgery was determined. Results: The mean total arc of elbow motion increased from 123±17 degrees preoperatively to 132±14 degrees postoperatively. The mean clinical score improved significantly from 133±24 to 177±27. Within the first year after surgery, 81.3% of the patients returned to active sports playing. However, 4 of 8 patients (50%) in which osteochondral peg fixation was performed for lesions of the lateral widespread type required reoperation. Conclusions: Our results indicate that osteochondral peg fixation and osteochondral autograft transplantation may improve elbow rating score, and may facilitate a return to active sports participation. However, osteochondral peg fixation may be insufficient for lesions of the widespread type because of their poor stability. The large lateral condyle lesions had a worse outcome, and future studies will need to develop improved treatment for these defects. Level of Evidence: Level IV (case series).

Facilitated Tendon-Bone Healing by Local Delivery of Recombinant Hepatocyte Growth Factor in Rabbits

PURPOSE This study was performed to evaluate the therapeutic effect of hepatocyte growth factor (HGF) on tendon-bone healing in a rabbit model. METHODS In adult rabbits the long digital extensor tendon was detached from the lateral femoral condyle, and the free end of the tendon was inserted into a tunnel drilled into the proximal tibial metaphysis. Cancellous bone obtained during drilling of the tibial hole was soaked in saline solution or solution containing 100-microg/mL human recombinant HGF and then transplanted into the bone tunnel. Junctional healing between the tendon and the bone was evaluated by histologic analysis and uniaxial load-to-failure testing at 2, 4, 6, 8, and 12 weeks after surgery. RESULTS In the saline solution-treated control group, Sharpey-like fibers, which connected the tendon graft and the bone tissue, appeared 6 weeks after treatment. At 8 weeks after treatment, maturation of lamellar bone was seen, and at 12 weeks, the adhesion between tendon and bone appeared to be supported by indirect insertion of fibrocartilaginous tissue, wherein the border between the fibrocartilaginous tissue and tendon or bone was significant. In the HGF-treated group, the fibrous tissues were parallel to the load axis, and lamellar bone and Sharpey-like fibers appeared as early as 4 weeks after treatment. At 12 weeks, junctional tissue, characterized by a continuous 4-layer structure of bone, calcified cartilage, fibrocartilage, and tendon, was regenerated by a direct insertion. On biomechanical testing, the HGF-treated group had significantly better biomechanical properties than the control group at 2 and 4 weeks. The histologic improvement caused by HGF treatment was associated with the biomechanical improvement. CONCLUSIONS Local administration of recombinant HGF promotes the adhesive healing process at the tendon-bone junction, both histologically and mechanically, after ligament reconstruction in a rabbit model. CLINICAL RELEVANCE Application of HGF may be considered as a new therapeutic approach to accelerate healing and rehabilitation after ligament reconstruction.

Oblique coronal and oblique sagittal MRI for diagnosis of anterior cruciate ligament tears and evaluation of anterior cruciate ligament remnant tissue

BACKGROUND The purpose of this study was to investigate the efficacy of additional oblique magnetic resonance imaging (MRI) for the diagnosis of anterior cruciate ligament (ACL) tear and evaluation of ACL remnant tissue. METHODS We retrospectively reviewed the records of 54 knees. Three independent readers evaluated the MR images by the use of three methods: orthogonal sagittal images only (method A); orthogonal sagittal and additional oblique sagittal images (method B); and orthogonal sagittal and oblique coronal images (method C). The sensitivity, specificity, and accuracy for the diagnosis of an ACL tear and the detection of the condition of the ACL remnant tissue by the use of each method were calculated in comparison with arthroscopic findings as the reference standard. RESULTS The arthroscopic records revealed 27 knees with intact ACLs and 27 with torn ACLs. Among the 27 knees with torn ACLs, 9 did not have continuous remnant tissue and 18 had certain remnant tissue attached to the femur or the posterior cruciate ligament. The specificities and accuracies of methods B and C for diagnosing an ACL tear were higher than those for method A. The sensitivity, specificity, and accuracy of method C for the detection of ACL remnant tissue were higher than those for method A and B. CONCLUSIONS Additional use of oblique MRI improved the accuracy of diagnosis of ACL tear and showed a reasonable level of efficacy in detecting ACL remnant tissue. LEVEL OF EVIDENCE Level IV (case series).

Effect of eccentric exercise on the healing process of injured patellar tendon in rats

BackgroundEarlier studies have reported positive results from eccentric training in patients with tendon disorders. The reasons for the beneficial clinical effects of eccentric training are not known. Vascularization followed by regression of the vasculature enhances the healing response of injured tendons. Eccentric exercise induces a more beneficial healing response than concentric exercise.MethodsSixty rats with patellar tendon injuries were divided into three groups: nonexercise controls (group N; n = 20); concentric exercise group (group C; n = 20); eccentric exercise group (group E; n = 20). Each rat was taught to run uphill or downhill for 14 days. Patellar tendons were removed 1, 4, 7, 10, and 14 days following injury. Vascular endothelial growth factor (VEGF), angiopoietin-1, and angiopoietin-2 were measured by reverse transcription polymerase chain reaction.ResultsIn group C, VEGF mRNA was increased 1 and 4 days following injury but was decreased on days 7, 10, and 14. In group E, VEGF mRNA was elevated only on day 1. In group N, VEGF mRNA remained at a low level throughout all 14 days. The angiopoietin-2/angiopoietin-1 ratio was higher for group C than for group E.ConclusionsIn the presence of VEGF, angiopoietin-1 promotes vessel stability, whereas angiopoietin-2 has the opposite effect. Eccentric exercise contributes to stabilized angiogenesis during the early phase of tendon injury. Conversely, concentric exercise, which induces destabilized angiogenesis, leads to a delayed healing response. Initiation of eccentric exercise immediately after tendon injury may help improve healing by reducing vascularity.

Effect of Heat Shock Preconditioning on ROS Scavenging Activity in Rat Skeletal Muscle after Downhill Running

The mechanisms of the protective effect conferred by heat shock preconditioning (HS) are currently unknown. The purpose of this study was to determine the effect of HS on muscle injury after downhill running and to address the mechanism of the effect. Female Wistar rats were assigned to three groups: HS, downhill running (E), and downhill running after heat shock preconditioning (HS + E). The HS and HS + E rats were placed in a heat chamber for 60 min (ambient temperature 42 +/- 1.0 degrees C) 48 h before downhill running. Reactive oxygen species (ROS) scavenging activity was determined by electron spin resonance (ESR), and heat shock protein 72 (HSP72) mRNA expression was measured in rat quadriceps femoris. Leukocyte infiltration and degenerated muscle fibers were determined histopathologically. ROS scavenging activity significantly increased at 3 days after HS (151 +/- 18%) and HSP72 mRNA expression increased immediately after HS (1750 +/- 1914%). No decrease in ROS scavenging activity was observed in the HS + E rats at 2 days after exercise compared with the E rats (102 +/- 9% vs. 79 +/- 5%). Degenerated muscle fibers in HS + E rats were significantly less than in E rats at 2, 3, and 7 days after exercise (0.8 +/- 1.0 vs. 2.8 +/- 1.6, 0.8 +/- 1.0 vs. 1.8 +/- 1.6, 0 vs. 0.3 +/- 0.6, respectively). These data demonstrated that HS can reduce muscle injury after downhill running, and this effect may be mediated by increased ROS scavenging activity. Furthermore, HS may protect the antioxidant defense system in skeletal muscle by enhancing the adaptive HSP72 mRNA response.

Contralateral anterior cruciate ligament injury after anterior cruciate ligament reconstruction: a case controlled study

PurposeThe purpose of this present study was to examine contralateral ACL injury cases after ACL reconstruction, to determine the characteristics of such injuries.MethodsWe performed a retrospective analysis of 24 patients with contralateral ACL injury after ACL reconstruction. The control group consisted of 200 cases with unilateral ACL injury. The following were examined in the contralateral group: timing of the contralateral ACL injury, and the situations of the initial and contralateral ACL injuries. The following items were compared between the contralateral and control groups: age at the time of initial injury, level of competitive sports using Tegner activity scores, knee anterior laxity (KT-1000), and the ratio (%) of affected to unaffected legs in the strengths of the knee extensor and flexor muscles 6 months after surgery.ResultsExamination of injury situations showed that approximately 70% of the contralateral group was injured in situations similar to those at their initial injuries. There were no significant differences between the two groups in age at the time of initial injury , Tegner activity scores, knee anterior laxity, and the strengths of the knee extensor, flexor muscles and H/Q ratio 6 months after reconstruction. But, the age at the time of initial injury trended to be low in contralateral group.ConclusionsKnee anterior laxity and muscle weakness of the reconstructed legs six months following surgery were not individually related to contralateral ACL injury occurring approximately two years after surgery.

Clinical evidence of a familial predisposition to anterior cruciate ligament injury

Background Several risk factors for anterior cruciate ligament (ACL) injury have been evaluated in the literatures. It is highly probable that many of the identified risk factors for ACL injury are passed through families. However few articles describe a familial predisposition to ACL injury. Objective To investigate whether there is a familial predisposition to ACL injury. Design Retrospective study. Methods The study group comprised 350 consecutive patients who underwent ACL reconstruction between January 2005 and September 2008. All patients were surveyed by telephone or written questionnaire about their family history (FH) of ACL injury, sports in which family members participated and mechanisms of injury. We also compared age, height, weight, Tegner activity score, general joint laxity, and tibial slope between the FH group (with a FH of ACL injury) and a control group (without a FH of ACL injury). Results Complete information was obtained from 335 of the 350 patients, 38 (11.3%) of whom had a FH of ACL injury. Two families had three members with ACL injuries. Among the 40 family members with ACL injuries, 38 (95%) had a non-contact ACL injuries, and 34 (85%) injured their ACL by the same mechanism as the related patient. Comparisons of the FH and control groups identified no significant differences with regard to age, height, weight, Tegner activity score, or general joint laxity, but tibial slope was significantly larger in the FH group than in the control group. Conclusion Our results indicate a high probability that many of the identified risk factors for ACL injury are passed through families. Screening tests for a FH of ACL injury thus could identify a population at increased risk of ACL injury who would benefit most from preventative neuromuscular training programs designed to reduce the risk of ACL injury.

Heparin versus Danaproid for Prevention of Venous Thromboembolism after Hip Surgery

Purpose. To compare the prevalence of deep vein thrombosis (DVT), pulmonary thromboembolism (PTE), and bleeding complications in patients receiving heparin or danaproid after hemiarthroplasty or osteosynthesis for hip fractures. Methods. 37 men and 138 women aged 47 to 100 (mean, 80) years underwent either hemiarthroplasty or osteosynthesis for hip fractures; 5 patients with dementia were excluded. All patients received preoperative elastic stocking and postoperative intermittent pneumatic compression. They were divided into 3 groups based on their admission period: controls (n=71), unfractionated heparin (n=44), and danaproid sodium (n=55). Drugs were administered from postoperative day 1 to 7. At day 7, all patients undertook radioisotope venography of the legs and lung perfusion scintigraphy. Results. In the control, heparin, and danaproid groups respectively, the DVT rates were 31%, 9.1%, and 5.5%, and the PTE rates were 5.6%, 4.5%, and 1.8%. Only the DVT rate in the control group was significantly higher than that in the heparin and danaproid groups. In the heparin group, one patient had gastrointestinal bleeding, 5 developed wound haematomas, and one had leakage from the drain site for 2 weeks. Conclusion. Danaproid sodium appeared more effective and safer than heparin, with no bleeding complications occurred.

Grafted tendon healing in femoral and tibial tunnels after anterior cruciate ligament reconstruction

Purpose. To evaluate tendon-to-bone healing after anterior cruciate ligament (ACL) reconstruction in the fibrous interzone (FIZ) of the femoral and tibial tunnels using magnetic resonance imaging (MRI). Methods. Five men and 5 women (mean age, 29 years) underwent arthroscopic ACL reconstruction by a single surgeon, using the semitendinosus and gracilis tendon. The tendon-to-bone healing in the FIZ was evaluated using sagittal and coronal MRI at 1, 3, 6, 9, 12, and 24 weeks, with the knee flexed at 60° and the tendon graft straight in both images. The signal intensity of the FIZ was visually assessed by comparing it with anatomic landmarks in the same patients knee, and classified into 4 grades. It was grade 3 when similar to that of the patellar tendon, grade 2 when similar to that of skeletal muscle, grade 1 when greater than that of muscle but less than that of joint fluid, and grade 0 when similar to that of joint fluid. At 24 weeks, subjective and objective functional outcomes were evaluated using the Lysholm score and the International Knee Documentation Committee score. Results. At 24 weeks, no patient had knee laxity. All patients had an International Knee Documentation Committee score of A, and their mean Lysholm score was 98.5. In the femoral tunnel, the FIZ did not change during the first 9 weeks (in particular the anterior part), but healing occurred rapidly thereafter. In the tibial tunnel, the FIZ healed over time in all locations, and healing was complete in the lateral and posterior parts at 12 weeks, and in all locations at 24 weeks. The mean signal intensity grade was significantly higher in the tibial than femoral FIZ at 3 to 12 weeks (p<0.01). Conclusion. After ACL reconstruction, the tendon-to-bone healing in the FIZ of the tibial tunnel was faster than that of the femoral tunnel.