Computer-assisted surgery and patient-specific instrumentation improve the accuracy of tibial baseplate rotation in total knee arthroplasty compared to conventional instrumentation: a systematic review and meta-analysis.

PURPOSE: To determine whether patient-specific instrumentation (PSI), computer-assisted surgery (CAS) or robot-assisted surgery (RAS) enable more accurate rotational alignment of the tibial baseplate in primary total knee arthroplasty (TKA) compared to conventional instrumentation, in terms of deviation from the planned target and the proportion of outliers from the target zone. METHODS: The authors independently conducted three structured electronic literature searches using the PubMed, Embase®, and Cochrane Central Register of Controlled Trials databases from 2007 to 2020. Studies were included if they compared rotational alignment of the tibial baseplate during TKA using conventional instrumentation versus PSI, CAS, and/or RAS, and reported deviation from preoperatively planned rotational alignment of the tibial baseplate in terms of absolute angles and/or number of outliers. Methodological quality of eligible studies was assessed by two researchers according to the Downs and Black Quality Checklist for Health Care Intervention Studies. RESULTS: Fifteen studies, that reported on 2925 knees, were eligible for this systematic review, of which 6 studies used PSI, and 9 used CAS. No studies were found for RAS. Of the studies that reported on angular deviation from preoperatively planned rotational alignment, most found smaller deviations using PSI (0.5° to 1.4°) compared to conventional instrumentation (1.0° to 1.6°). All studies that reported on proportions of outliers from a target zone (± 3°), found lower rates of outliers using PSI (0 to 22%) compared to conventional instrumentation (5 to 96%). Most studies reported smaller angular deviation from preoperatively planned rotational alignment using CAS (0.1° to 6.9°) compared to conventional instrumentation (1.1° to 7.8°). Of the studies that reported on proportions of outliers from a target zone (± 3°), most found fewer outliers using CAS (10 to 61%) compared to conventional instrumentation (17 to 78%). CONCLUSION: This systematic review and meta-analysis revealed that both CAS and PSI can improve the accuracy of rotational alignment of the tibial baseplate by decreasing angular deviation from the preoperatively planned target and reducing the proportion of outliers from the target zone. The clinical relevance is that PSI and CAS can improve alignment, though the thresholds necessary to grant better outcomes and survival remain unclear. LEVEL OF EVIDENCE: IV.

Topical co-delivery of platelet rich fibrin and tranexamic acid does not decrease blood loss in primary total knee arthroplasty compared to the standard of care: a prospective, randomized, controlled trial.

PURPOSE: The purpose of this study was to evaluate the efficacy of intra-operative co-administration of tranexamic acid (TA) and platelet rich fibrin (PRF) using a proprietary co-delivery system on the amount of blood loss, early functional outcomes and wound complications after primary total knee arthroplasty (TKA). The intervention was compared to the standard of care (combined intravenous & topical TA) in a prospective, randomized, blinded setting. METHODS: 80 patients undergoing primary cemented TKA without tourniquet were prospectively randomized into control (combined intravenous and topical TA) and PRF (intra-venous TA and co-delivery of topical PRF and TA) groups after informed consent. Total blood loss, drainage blood loss, knee range of motion, VAS pain scores, length of stay and wound complications were analysed. Data collection was performed in a double blind manner on days 1, 3 and 21. RESULTS: There was no statistically significant difference in drainage blood loss (550 ml vs. 525 ml, p = 0.643), calculated total blood loss on day 1 (401 ml vs. 407 ml, p = 0.722), day 3 (467 ml vs 471 ml, p = 0.471) and day 21 (265 ml vs. 219 ml, p = 0.082) between the PRF and control groups respectively. The PRF group had a small but statistically significant increase in median knee extension in the early post-operative period, however this difference evened out at 3 weeks. No significant difference could be demonstrated between the PRF and control groups in length of stay, VAS pain scores, narcotic usage, wound complications and knee flexion at all time points. CONCLUSIONS: The topical co-delivery of PRF and TA does not significantly decrease blood loss in primary TKA compared to the standard of care. Slightly better active knee extension in the first 3 postoperative days can be achieved, however this benefit is not clinically relevant. LEVEL OF EVIDENCE: I, Therapeutic study.

Twenty-one sports activities are recommended by the European Knee Associates (EKA) six months after total knee arthroplasty.

PURPOSE: To elaborate recommendations for sports participation following TKA among the members of the European Knee Associates (EKA). METHODS: A prospective online survey was conducted among the members of the European Knee Associates (EKA). The European Knee Associates (EKA) are a section of the European Society of Sports Traumatology, Knee Surgery and Arthroscopy (ESSKA). The survey investigated recommendations for 47 sports disciplines. Possible answers were: allowed, allowed if experienced, not allowed, no opinion. The survey was conducted separately for 4 specific time frames: within 6 weeks after TKA; 6-12 weeks after TKA; 3-6 months after TKA; and more than 6 months after TKA. Consensus among the respondents was then analyzed. RESULTS: EKA members (N = 120) participated in the survey. A high level of consensus was reached for a recommendation to allow 5 different sports in the first 6 weeks after TKA, 7 sports 6-12 weeks after surgery, 14 sports 3-6 months after TKA, and 21 out of 47 activities 6 months after surgery. In the first 6 weeks after TKA walking, stair climbing, swimming, aqua fitness, and static cycling were recommended. Six to twelve weeks after TKA, cycling on level ground and yoga were recommended in addition to the aforementioned activities. Further sports activities recommended beyond 12 weeks after TKA were: tennis doubles, golf, fitness/weight lifting, aerobics, hiking, Nordic walking and sailing. The sport for which the recommendation was "not allowed" following TKA was squash. CONCLUSION: The number of sports recommended by EKA surgeons increases stepwise over the postoperative time frames. The findings are regarded as clinically relevant as they may serve as a basis for answering patient questions on timing and giving recommendations for the resumption of sports activities following standard primary TKA and should be individualized by surgeons for their patients' expectations and goals. LEVEL OF EVIDENCE: V.

Prioritising of hip and knee arthroplasty procedures during the COVID-19 pandemic: the European Hip Society and the European Knee Associates Survey of Members.

PURPOSE: During the COVID-19 pandemic there has been a massive reduction of arthroplasty services due to reallocation of hospital resources. The unique challenge for clinicians has been to define which arthroplasty patients most urgently require surgery. The present study aimed to investigate priority arthroplasty procedures during the pandemic and in the reinstatement period from the surgeon's perspective. MATERIAL AND METHODS: An online survey was conducted among members of the European Hip Society (EHS), European Knee Associates (EKA) and other invited orthopaedic arthroplasty surgeons (experts) from across the world. The survey consisted of 17 different arthroplasty procedures/indications of which participants were asked to choose and rank the most important 10. RESULTS: Four hundred and thirty-nine arthroplasty surgeons from 44 countries responded. The EHS and EKA had a 43% response rate of members. In weighted average points, the majority of respondents (67.5 points) ranked 'acute fractures requiring arthroplasty (Periprosthetic fractures, THA/hemi-arthroplasty for femoral neck fractures)' as priority indication number one, followed by 'first-stage explantations for acute PJI (periprosthetic joint infection)' in second place and priority indication (45.9 points) three as 'one-stage revision for acute PJI' (39.7 points). CONCLUSIONS: There was agreement that femoral neck fractures, periprosthetic fractures, and acute infections should be prioritised and cannot be postponed in the setting of the COVID-19 pandemic. As arthroplasty procedures are being resumed in most countries now, there has also been a relaxation of lockdown rules in most countries, which might cause a so-called second wave of the pandemic. Therefore, the results of the current study present a proposal by experts as to which operations should be prioritised in the setting of a second wave of the pandemic.

Intra-articular zoledronic acid in a rat osteoarthritis model: significant reduced synovitis may indicate chondroprotective effect.

PURPOSE: The aim of this experimental study was to evaluate the effect of intra-articular application of zoledronic acid (ZA) on joint cartilage and synovial tissue following induction of knee osteoarthritis (OA) in a rat model. METHODS: An OA model was created by anterior cruciate ligament transection (ACLT) in the right knees of 48 adult Wistar albino rats. The rats were randomized into a study and control groups, each including 24 rats, and 10 µg of ZA was injected in 0.1 ml of sterile saline to 24 animals in the study group on the first day to operation and was repeated weekly until the rats were killed. The same volume of sterile saline was injected with the same schedule to the control group. Eight rats from both the study and control groups were killed, each time, on the 4th day, the 3rd week, and the 6th week after the operation. The groups were compared based on the histological scores of synovitis and cartilage destruction and the evaluation of serum markers. RESULTS: Histological score indicates progression of synovitis was significantly less in the study group (p = 0.047). There was significant increase in the mean Mankin cartilage damage score in the control group (p = 0.021), while no significant change was found in the study group. When the two groups were compared over time, no statistically significant difference was detected in total histological scores, although there was a 47 % less incidence of cartilage tissue damage in the study group and better cartilage structure and tide mark integrity scores were also detected in the study group (p = 0.017 and p = 0.021, respectively). CONCLUSION: Intra- articular zoledronic acid may suppress synovial inflammation. Furthermore, Zoledronic Acid does not reduce cartilage degeneration in early osteoarthritis models, but may provide some chondroprotective effect in ACLT- induced knee osteoarthritis model in rats.

Trends in unicompartmental knee arthroplasty among 138 international experienced arthroplasty knee surgeons.

Purpose: Unicompartmental knee arthroplasty (UKA) is an established option for treating isolated unicompartmental knee osteoarthritis (OA), but controversies still exist about patient selection, indications, perioperative management and alignment goals. This survey was designed to understand the current trends of experienced arthroplasty knee surgeons performing UKA. Methods: An online questionnaire was created with SurveyMonkey® to assess global tendencies in the utilization of UKA. A link to the survey was shared with all ESSKA (European Society for Sports Traumatology, Knee Surgery and Arthroscopy) members. The questionnaire consisted of free and multiple-choice questions and was divided into four sections: demographic information, the surgical activity of the respondents, indications for surgery and postoperative alignment goals. Results: A total of 138 ESSKA members from 34 different countries completed the survey. A total of 81 % of the responders performed fewer than 50 UKAs per year; 53 % of UKAs represented less than 20 % of their knee replacements; 71 % used mainly or only fixed-bearing implants; 81 % performed UKA in a shorter time compared to TKA; and 61 % and 72 % were interested in custom-made UKA and robotics, respectively. Thirty-six percent considered a minimum postoperative alignment of 0° for medial UKA, and 32 % considered 10° as the maximum valgus deformity for lateral UKA. Fifty-five percent had no minimum age cut-off, 47 % had no BMI cut-off, and 57 % believed TKA was better than UKA in knees with concomitant high-grade patellofemoral OA. Approximately 50 % of the surgeons desired a coronal alignment that was the same as the predegeneration alignment. Conclusion: A high level of agreement was reached regarding the following: preference for fixed-bearing UKAs, lower surgical time for UKA compared to TKA, interest in custom-made and robotic UKAs, no age and weight cut-off, TKA preferred in the presence of patellofemoral OA, and a final alignment goal of the predegenerative state both for medial and lateral. There was no agreement regarding length of stay, rehabilitation protocol, preoperative varus and valgus cut-off values, and treatment in cases of absence of anterior cruciate ligament or previous osteotomy.

Safety, Efficacy, and Cost-Effectiveness of Simultaneous Bilateral Arthroscopic Bankart Repair for Bilateral Shoulder Instability.

Background: Bilateral shoulder instability and Bankart lesions are not rare and frequently require surgical treatment. Bilateral instability may be treated with either a single-stage, simultaneous bilateral Bankart repair or 2-stage surgery. Purpose/Hypothesis: To compare simultaneous bilateral arthroscopic Bankart repair to 2-stage repair in terms of clinical outcomes and hospitalization costs. It was hypothesized that simultaneous repair would provide clinical outcomes similar to those of 2-stage Bankart repair while yielding lower hospitalization costs. Study Design: Cohort study; Level of evidence, 3. Methods: Patients who underwent simultaneous bilateral arthroscopic Bankart repair (group 1) were matched by age, sex, and injury type to control patients who had unilateral Bankart repair (group 2). All patients were operated on by the same surgeon in the same institution between 2007 and 2017 and had a minimum follow-up duration of 24 months. Patients with inflammatory arthritis, metabolic/malignant disease, previous shoulder surgery, a glenoid bone loss ≥25%, or off-track Hill-Sachs lesion were excluded. The 2 groups were compared in terms of pre- and postoperative Western Ontario Shoulder Instability Index (WOSI) scores, hospitalization costs, complications, and recurrent instability. The hospitalization cost of group 2 was multiplied by 2 to create a projection of the estimated cost of 2 sequential unilateral Bankart repairs. Results: The study population comprised 48 patients (38 men [79.17%] and 10 women [20.83%]; mean age, 25.5 years at surgery and 22.75 years at first dislocation). Group 1 included 32 shoulders in 16 patients, while group 2 consisted of 32 shoulders in 32 patients. The mean hospitalization cost (in 2020 US dollars) was $26,010 ± $1455 for group 1 and $33,591 ± $1574 for group 2 (P < .001). Both groups had improved WOSI scores after surgery and achieved similar scores at the latest follow-up. There was 1 redislocation in each group (3.13%). No surgery- or anesthesia-related/medical complications were recorded in either group. Conclusion: For bilateral shoulder instability, clinical outcomes of simultaneous bilateral arthroscopic Bankart repair were similar to those of 2-stage repair; however, lower hospitalization costs were seen after simultaneous bilateral repair compared with 2-stage surgery.

Extensor mechanism ruptures.

Native patellar tendon injuries are seen in younger patients compared to quadriceps tendon ruptures. Up to a third of the patients may have local (antecedent tendinopathy and cortisone injections) or systemic risk factors (obesity, diabetes, hyperparathyroidism, chronic renal failure, fluoroquinolone or statin use) of injury, these are more frequent in bilateral disruptions. Complete extensor mechanism disruptions should be repaired surgically. Although isolated primary repair has been reported to have good outcomes in younger patients with acute tears and good tendon quality, augmentation of the repair with autograft, allograft or synthetic material should be considered in patients with poor tendon quality, chronic tears or tendon defects. High rates of return to work/sports have been reported in native patellar and quadriceps tendon tears, with re-rupture rates <5%. Extensor mechanism disruptions in patients with a total knee arthroplasty are challenging due to older age, systemic co-morbidities and poor local conditions, resulting in inferior outcomes compared to native extensor mechanism injuries. Some form of augmentation with autograft, allograft or synthetics is advisable in all cases. Salvage procedures such as whole extensor mechanism allografts provide acceptable outcomes in multiply operated knees with extensive bone and soft tissue deficits.

Resuming hip and knee arthroplasty after COVID-19: ethical implications for wellbeing, safety and the economy.

Reinstating elective hip and knee arthroplasty services presents significant challenges. We need to be honest about the scale of the obstacles ahead and realise that the health challenges and economic consequences of the COVID-19 pandemic are potentially devastating.We must also prepare to make difficult ethical decisions about restarting elective hip and knee arthroplasty. These decisions should be based on the existing evidence-base, reliable data, the recommendations of experts, and regional circumstances.

Knee joint synovial cyst following total knee arthroplasty with bone allograft.

Allograft has been shown to be highly successful for managing large osseous defects in total knee arthroplasty. We report a 68-year-old woman in whom a bone allograft had been used during total knee arthroplasty owing to a massive segmental medial tibia plateau defect 4 years earlier. Eighteen months after surgery, a 10x10 cm knee synovial cyst was detected by computed tomography scanning on the anteromedial side of the tibial plateau, and an en-bloc surgical excision was performed. At 36-month follow-up, a 16x12 cm cyst was found. Excision was again performed with removal of the allograft and application of an autologous iliac graft. After allograft removal, clinically and radiologically satisfactory results were achieved at the final follow-up.

Analysis of outcomes for surgically treated hip fractures in patients undergoing chronic hemodialysis.

BACKGROUND: Hip fractures in patients with end-stage renal disease are associated with frequent complications. This study analyzed clinical outcomes for patients on chronic hemodialysis who sustained hip fractures and were treated with a variety of fracture repair methods. METHODS: Twenty-nine patients with thirty-two hip fractures were analyzed in three groups. Group 1 consisted of eleven hips in eleven patients with an intertrochanteric fracture that was treated with internal fixation; Group 2, thirteen hips in ten patients with a femoral neck fracture that was treated with screw fixation; and Group 3, eight hips in eight patients with a femoral neck fracture that was treated with hemiarthroplasty. The outcomes and early and late complications were recorded for each group. Survivorship analysis was performed, and the mortality and complication rates for the groups were compared. RESULTS: In Group 1, eight complications occurred in six hips and nonunion developed in five hips. In Group 2, sixteen complications developed in eleven hips. Union was achieved in two of the thirteen hips, nine hips had nonunion, and two hips had osteonecrosis develop. In Group 3, only one hip had early complications, there were no late complications, and three patients died. The mean duration of follow-up was twenty-three months, and the overall mortality rate was 45%. There were no significant differences among the groups with respect to the cumulative survival proportions. Regression analysis of age, sex, and total hemodialysis duration in relation to mortality risk revealed that only age had a significant influence on mortality (p = 0.019). CONCLUSIONS: Surgical treatment of hip fractures in patients with end-stage renal disease who are on chronic hemodialysis is associated with frequent complications and a high mortality rate. Osteosynthesis is an acceptable option for treating intertrochanteric fractures and nondisplaced femoral neck fractures, but displaced femoral neck fractures should be treated with hemiarthroplasty.

Necrotizing soft-tissue infection of a limb: clinical presentation and factors related to mortality.

BACKGROUND: Necrotizing fasciitis is a rare and often fatal soft-tissue infection. Prompt diagnosis and immediate aggressive surgical debridement of all compromised tissues are critical to reducing morbidity and mortality in these rapidly progressive infections. The purpose of this study was to analyze the clinical presentation and evaluate factors that determine mortality associated with this uncommon surgical emergency. METHODS: The study retrospectively investigated the medical records of 22 patients who were diagnosed and treated for necrotizing fasciitis of the lower extremity, 14 of whom had involvement of the foot (nine patients) or foot and ankle (five patients) at our hospital. The data collected for each of the 22 patients were age, sex, underlying systemic factors, location of infection, duration of symptoms, portal of entry of infection, initial diagnosis on admission, physical, radiographic and laboratory findings, microbiological cultures, the type of therapy used (debridement or amputation), treatment outcome, and number of days in the hospital. RESULTS: A total of 23 extremities of 22 consecutive patients with necrotizing fasciitis who underwent surgical debridement or amputation were retrospectively reviewed. Radical surgical debridement was done in 16 extremities initially, and this treatment was repeated a mean of two times (range one to four debridements) to completely remove all the necrotic tissue. Nine patients (41%) required below-knee or above-knee amputation. There were three deaths, one related directly to sepsis and organ failure, one due to gastrointestinal hemorrhage, and one caused by pulmonary embolism. There were no significant differences between patients who had the amputations and those who did not with respect to mortality rate or age (p = 0.538 and p = 0.493, respectively). Those who died were significantly older than the survivors (p = 0.038). CONCLUSIONS: The diagnosis of necrotizing fasciitis should be considered for any individual who has unexplained limb pain, especially if that person has diabetes mellitus or chronic liver disease. There was no difference in mortality rates between patients with or without amputation. The primary treatment is early and aggressive debridement of involved skin, subcutaneous fat, and fascia.

Arthroscopic treatment of solitary benign intra-articular lesions of the knee that cause mechanical symptoms.

PURPOSE: Most cases of knee locking and giving-way are caused by meniscal tears, loose bodies, or chondral lesions. Intra-articular benign tumors or tumor-like lesions can present with symptoms that resemble acute mechanical derangement. From a database of 2,200 arthroscopic interventions, 19 cases of intra-articular masses that presented with catching and locking symptoms in the knee were retrospectively analyzed. TYPE OF STUDY: Case series. METHODS: Our review revealed 33 patients with benign intra-articular masses in the knee joint. Nineteen of these individuals had sought medical attention for mechanical symptoms of catching or locking. The other 14 patients had a variety of symptoms including pain, swelling, and limitation of knee motion, but did not have mechanical symptoms. Age, sex, history of trauma, knee pain and effusion, medical illnesses, physical examination, arthroscopic findings, and pathologic findings were noted. RESULTS: The average age of the 6 male and 13 female patients was 37.5 years (range, 18 to 58 years). Preoperative magnetic resonance imaging confirmed the diagnosis in 7 cases and 12 cases were diagnosed during knee arthroscopy. The mean follow-up time after surgery was 52.5 months (range, 6 to 120 months). Pathologic examination of the lesions revealed 15 cases of localized pigmented villonodular synovitis (79%), 1 lipoma arborescens (5%), 1 pseudocyst (5%), and 2 nonspecific synovial masses (11%). None of the lesions showed malignant transformation. CONCLUSIONS: Solitary benign intra-articular lesions should be considered a rare cause of mechanical knee symptoms. Localized pigmented villonodular synovitis originating from the extensor mechanism or fat pad is the most common solitary intra-articular mass lesion in the knee and usually arises in the patellofemoral compartment. Recurrence has not occurred in our series, which includes 14 of 19 patients with greater than 24 months follow-up. LEVEL OF EVIDENCE: Level IV.

Mechanical strength of four different biceps tenodesis techniques.

PURPOSE: The aim of this study was to compare the biomechanical properties of 4 different biceps tenodesis techniques. TYPE OF STUDY: Biomechanical experiment. METHODS: Four groups of fresh sheep shoulders (28 total) with similar shape characteristics were used. Biceps tenodesis was performed using the following techniques: group 1 (n = 7), tunnel technique; group 2 (n = 7), interference screw technique; group 3 (n = 7), anchor technique; and group 4 (n = 7), keyhole technique. Each construct was loaded to failure and the groups were compared with respect to maximum load in Newtons and deflection at maximum load in millimeters. The results were statistically analyzed with 1-way analysis of variance, the Bonferroni post hoc test and the Student t test or the nonparametric Mann-Whitney U test. RESULTS: The calculated average maximum loads were 229.2 +/- 44.1 N for the tunnel technique, 243.3 +/- 72.4 N for the interference screw, 129.0 +/- 16.6 N for the anchor technique, and 101.7 +/- 27.9 N for the keyhole technique. Statistical testing showed no statistically significant differences between groups 1 and 2, groups 3 and 4, or groups 2 and 3 with respect to maximum load and deflection at maximum load (P = .09/P = .49, P = .41/P = .79, and P = .06/P = .82 for load/deflection in the 3 comparisons, respectively). However, all other group comparisons revealed significant differences for both parameters (group 1 v group 4 [P < .01/P < .01]; group 1 v group 3[P < .01/P = .01]; and group 2 v group 4 [P = .007/P = .003]). CONCLUSIONS: The strongest construct was made with the interference screw technique, followed by the tunnel, anchor, and keyhole techniques. There were no statistically significant differences between the interference screw and tunnel techniques with respect to maximum load or deflection at maximum load. CLINICAL RELEVANCE: Although it is difficult to extrapolate in vitro data to the clinical situation, the interference screw technique has better initial biomechanical properties and may produce improved clinical outcomes.

Arthroscopic debridement and grafting of an intraosseous talar ganglion.

We report the case of a 41-year-old man with right ankle pain and swelling who had an intraosseous talar ganglion in the medial part of talar dome. A surgical procedure was performed using the 3-portal arthroscopic approach. The softened chondral surface was removed and the content of the cyst was discharged arthroscopically. The sclerotic rim was abraded until the bleeding spongious layer was seen. A grafting procedure was also performed arthroscopically. A trocar was introduced into the defect from the superomedial portal. Autografts were impacted using a cylindrical rod through the trocar into the defect. The clinical and radiologic results at the 1-year follow-up were satisfactory. We encountered no complications postoperatively. We conclude that arthroscopic debridement and grafting of an intraosseous ganglion adjacent to the articular surface may be a better option compared with open surgery.

Hallucal sesamoid osteonecrosis: an overlooked cause of forefoot pain.

Four cases of osteonecrosis of hallucal sesamoids are reported here. Surgical excision of necrotic sesamoid tissue yielded satisfactory results, with the patients reporting no residual pain. Although it has not been frequently addressed in the literature, avascular necrosis of the sesamoid bones should be considered in the differential diagnosis of persistent forefoot pain.

Arthroscopic-assisted percutaneous screw fixation of select patellar fractures.

PURPOSE: To describe a technique of arthroscopic-assisted reduction and percutaneous cannulated screw fixation for displaced patellar fractures and to present the results of 5 cases. TYPE OF STUDY: Case series. METHODS: Five patients (3 male, 2 female) with displaced patellar fractures treated with an arthroscopic-assisted reduction and percutaneous cannulated screw fixation were prospectively analyzed. The mean age was 53 years (range, 27 to 74 years). All fractures were fixed with at least 2 4-mm cannulated screws under arthroscopic visualization. Cerclage wiring through the cannulated screws was necessary in 2 patients with osteopenic bone. Controlled passive range of motion exercises were started on the first postoperative day. Full weight bearing with an immobilizer-type brace was allowed as tolerated. The mean follow-up was 28 months (range, 24 to 35 months). The patients were evaluated with Lysholm II scores, clinical examination, knee range of motion, thigh circumference measurements, and radiographs. RESULTS: All fractures healed uneventfully. The mean Lysholm II score was 84.8 (range, 75-96). All but 1 patient regained full knee range of motion. A mean quadriceps atrophy of 0.8 cm compared with the contralateral side was seen in unilateral cases. There was no implant failure or infection. CONCLUSIONS: Arthroscopic-assisted reduction and percutaneous cannulated screw fixation is appropriate for displaced transverse patellar fractures without major separation and comminution. Longitudinal or oblique fractures, even if there are more than 2 major fragments, are amenable to arthroscopic techniques, providing the fragments are large enough to be fixed with screws. This technique is minimally invasive and does not disturb the vascular supply of patella. It allows clear visualization of the reduction and stability of the fracture, and facilitates early postoperative range of motion exercises. This method is not suitable for highly comminuted fractures or transverse fractures with major separation that are accompanied by rupture of the extensor mechanism.

Effects of methylprednisolone and betamethasone injections on the rotator cuff: an experimental study in rats.

Thirty-one female Sprague-Dawley rats were used to determine the effects of subacromial corticosteroid injections on the rotator cuff. The injection technique was tested in 6 animals, which were excluded from the study. The remaining 25 rats were randomly divided into three groups of 8 animals each; a single rat received no injections. Every other week for 8 weeks, one shoulder in each rat was injected with methylprednisolone, betamethasone, or saline in a dosage equivalent to that used in humans. The supraspinatus and infraspinatus tendons were removed 10 days after the last injection and evaluated. There were no pathologic changes in the tendons injected with saline. In 43% of the methylprednisolone-treated rats and 29% of the betamethasone-treated rats, the tendons were abnormally soft and light-colored. In 43% of the methylprednisolone group and 71% of the betamethasone group, fragmentation of collagen bundles and inflammatory cell infiltration were evident. Subacromial injections of methylprednisolone or betamethasone repeated frequently can cause deleterious changes in the normal structure of the rat rotator cuff. In light of these findings, therapy for subacromial impingement syndrome of the shoulder with frequent, repeated steroid injections is potentially harmful.

Tunnel enlargement after arthroscopic anterior cruciate ligament reconstruction: comparison of bone-patellar tendon-bone and hamstring autografts.

Bone tunnel enlargement associated with anterior cruciate ligament (ACL) reconstruction has recently become a topic of interest in the literature. This association was examined, along with the effect of femoral and tibial tunnel enlargement on the clinical results of ACL reconstruction performed with either bone-patellar tendon-bone (BPTB) or hamstring (HST) autografts. Forty-six patients underwent arthroscopic ACL reconstruction (23 receiving BPTB autograft and 23 HST) between March 1999 and July 2001. Thirty patients (13 receiving BPTB autograft and 17 HST) completed the last clinical and radiologic evaluations and were included in the study. The mean age of patients in the HST group was 29.8 years (range 18-39) and that in the BPTB group was 27.6 years (range 20-37). The mean follow-up period was 24.6 months (range 12-36) in HST group and 18.5 months (range 12-40) in BPTB group. The effect of tunnel enlargement on the clinical results was evaluated by comparing preoperative and postoperative Lysholm, Tegner, and International Knee Documentation Committee scores and ligament laxity measurements between and within the groups. Postoperative femoral and tibial tunnel diameters in both groups were significantly larger than their corresponding preoperative tunnel diameters. In an intergroup evaluation, the enlargement of the tibial tunnel was similar in both groups (P=.556), but the femoral tunnel diameter was significantly larger in the HST group than in the BPTB group (P>.001). Preoperative laxity of the knees significantly improved after the operations in both groups, but no difference between the groups was evident at the final follow-up visit. No correlation between tunnel widening and the clinical results of the BPTB and HST procedures was observed.