Postarthroscopy osteonecrosis of the knee.

PURPOSE: Spontaneous subchondral osteonecrosis of the knee joint confined to a localized area of one condyle can occur after arthroscopic procedures. Meniscal tears, arthroscopic meniscectomy, and radiofrequency chondroplasty are aetiological factors in the development of osteonecrosis. The aim of this study was to investigate whether the incidence of osteonecrosis increased when mechanical or radiofrequency chondroplasty was used in conjunction with arthroscopic meniscectomy. METHODS: In this prospective clinical trial, arthroscopic meniscectomy was the primary treatment in 75 patients (mean age 40 ± 13) with stage II and III degenerative changes on the articular cartilage. Patients had to meet the following criteria: 1) have preoperative MRI and plain film radiographs showing no evidence of osteonecrosis; 2) be symptomatic for at least 6 weeks before the preoperative MRI; and 3) have arthroscopically confirmed stage II or III chondral lesion. A preoperative MRI was performed for all patients. For treatment of chondral lesions, debridement with a shaver or chondroplasty with a monopolar RF energy system was used. Patients were divided into three treatment groups. Partial meniscectomy of the medial or lateral (or both) menisci was performed on all patients, but patients in group 2 additionally received mechanical debridement of the chondral lesion, and those in group 3 were additionally treated with RF chondroplasty. Patients in group 1 were treated with partial meniscectomy alone. Patients were re-examined after 6 months, at which time a repeat MRI was performed. RESULTS: Development of osteonecrosis was detected during the postoperative MRIs of five patients: two in group 1, two in group 2, and one in group 3. CONCLUSION: The addition of mechanical or RF chondroplasty to meniscectomy did not increase the number of patients with osteonecrosis. Also, RF chondroplasty, which is commonly proposed to be an aetiological factor, resulted in a decrease in the number of patients that developed osteonecrosis. LEVEL OF EVIDENCE: II.

[The effectivity of magnetic resonance imaging findings in the diagnosis of bucket handle meniscal tears]. / Kova sapi menisküs yirtigi tanisinda manyetik rezonans görüntüleme bulgularinin etkinligi.

OBJECTIVES: This study aims to test the efficacy of magnetic resonance imaging (MRI) evaluation by a group who were blinded to the arthroscopic diagnosis in patients with known bucket handle meniscal tears. PATIENTS AND METHODS: In this study, MRI scans of 28 patients who were operated due to bucket handle meniscal tear with sufficient documentation were evaluated. Radiographic evaluation was performed by two different groups, including an orthopedist and radiologist. In the first group, evaluation of MRI scans was performed by the specialists who were aware of the arthroscopic diagnosis and marked the defined MRI signs of bucket handle meniscal tear. In the second group, evaluation was done, remaining blinded to the diagnosis, with only initial complaints at admission. The second group also evaluated the MRI scans and marked the pathologic signs. The sensitivity of radiological signs marked by both groups was compared. Invariables were found using blinded evaluation. RESULTS: Double posterior cruciate ligament and free fragment in the intercondylar notch were invariable sensitivities found in the MRI scans by blinded evaluation. The sensitivity of coronal truncation, anterior flip and any free fragment signs were significantly decreased in the setting of blinded evaluation. CONCLUSION: Preoperative differentiation of reparable bucket-handle tears from irreparable is of utmost importance. As meniscal repair improves knee stability and functional results, surgical repair of meniscal injuries particularly in younger individuals who are scheduled for anterior cruciate ligament reconstruction have a positive effect on clinical outcomes.

Revision of the failed pedicle screw in osteoporotic lumbar spine: biomechanical comparison of kyphoplasty versus transpedicular polymethylmethacrylate augmentation.

OBJECTIVES: In this study, we aimed to compare of kyphoplasty versus transpedicular polymethylmethacrylate (PMMA) augmentation biomechanically in the revision of the failed pedicle screw in osteoporotic lumbar spine. MATERIALS AND METHODS: Bone mineral density (BMD) of lumbar vertebrae collected from four bovines were measured. Each vertebra was decalcified with hydrochloric acid solution to obtain osteoporotic specimens. Primary polyaxial pedicle screws were inserted into the pedicles and pulled out until they failed. The pullout strength results of all specimens were recorded. Revision pedicle screws were randomly inserted into the same pedicles by either pedicle hole PMMA augmented (group 1) or kyphoplasty (Xvoid™) PMMA augmented pedicle screws (group 2). The pullout strength results of all specimens were re-recorded. RESULTS: The mean BMD significantly decreased from 1.686 ± 227.9 g/cm(2) to 1.432 ± 157.1 g/cm(2) following decalcification (p<0.001). In group 1, the mean pullout strength of primary screws significantly decreased from 3443 ± 1086 N/m(2) to 2088 ± 924 N/m(2) following pedicle screw augmentation (p=0.006). In group 2, the mean pullout strength of primary screws decreased from 3702 ± 1063 N/m(2) to 3664 ± 1057 N/m(2) following kyphoplasty augmentation (p=0.934). Pedicle screw augmentation group achieved significantly lower pullout strength values than kyphoplasty pedicle hole augmentation group (p=0.002). CONCLUSION: Although pedicle hole PMMA augmentation is the gold standard for the failed screws in an osteoporotic bone, kyphoplasty augmented pedicle screw seems to be more effective method increasing the pullout strength.

Clamp fixation to prevent unfolding of a suture knot decreases tensile strength of polypropylene sutures.

PURPOSE: Although sutures evolved in last decade and the product spectrum broadened largely, they can be still classified into two: monofilament and multifilament. Sutures are the mainstay of orthopedic procedures like fascial closures, tendon repairs or tenodesis. In every repair, a suture loop is created. This suture loop is prone to failure due to suture elongation, knot slip and suture breakage. As the knot is the stress riser in a suture loop, the majority of acute loop failure occurs just adjacent to the knot. Monofilament sutures have higher bending stiffness and tendency to untie than multifilament sutures. The first throw of monofilament sutures have tendency to untie, which decrease loop tension and result in loss of achieved tissue approximation. METHODS: Although a common practice is to fix the first throw via a clamp before the locking one is tied, it can be hypothesized that a potential deforming effect can lead to a decrease in ultimate failure load of a monofilament suture loop. RESULTS: Fixing the first throw significantly reduced the ultimate failure load of monofilament nonabsorbable polypropylene sutures (Prolene) (62.2 ± 8 N vs. 72.7 ± 9 N, p = 0.019). The ultimate failure load achieved by monofilament sutures Polyglyconate (Maxon) and Nylon (Ethilon) and braided absorbable Polyglactin (Vicryl) were not affected by fixing the first throw. CONCLUSION: Under microscopic examination, polypropylene sutures were found to be deformed by clamp fixation, while the others were not. Polypropylene sutures can be easily damaged when it is fixed by a clamp during knot tying. Presented data demonstrated that in real surgical situations clamp fixation of polypropylene knots can damage the suture loop and carry the risk of acute failure of repair site during early rehabilitation.

Comparison of two techniques in achieving planned correction angles in femoral subtrochanteric derotation osteotomy.

Increased femoral anteversion in cerebral palsy alters biomechanics of gait. Femoral subtrochanteric derotational osteotomies are increasingly performed to improve gait in cerebral palsy. The amount of angular correction can be determined and planned preoperatively but, accuracy in achieving planned angular correction has not been tested experimentally before. The aim of this study was to evaluate the accuracy of the two techniques in achieving planned angular correction. Sixteen dry femora were used in this study. Specimens in both groups were derotated to achieve a desired amount of correction with two different techniques, consecutively. In technique one, the cross section of the femur was assumed to be circular and the desired amount of angular correction was calculated and expressed in terms of surface distance by a geometric formula (surface distance=2×π×radius of femur). In both groups, derotations were made based on this surface distance calculation. Consecutively the same specimens were derotated by pins and guide technique. Femoral anteversion of specimens were measured before and after derotation by computerized tomography. There was a statistically significant differance in planned and achieved correction angles (P=0.038) in both subgroups derotated by the surface distance technique. When the two techniques were compared, there was significant difference (P=0.050) between high magnitude correction subgroups (subgroups 2 vs. 4). In conclusion, the results of this study highlighted the difficulty in achieving accurate derotation angles. Derotations based on guide-pins technique yielded more accurate results than derotations based on surface distance technique. In addition, surface diameter technique was not suitable when higher degrees of derotations are needed. In achieving a planned derotation angle two techniques are described for accuracy. Both the techniques have potential pitfalls resulting in malrotations. Surgeons must be aware of these obstacles and try to avoid them.

[The efficacy and safety of limited incision technique in carpal tunnel release]. / Karpal tünelin gevsetilmesinde sinirli insizyon tekniginin etkinligi ve güvenilirligi.

OBJECTIVES: This study aims to determine the safety and symptomatic and functional efficacy of median nerve decompression with 3 cm limited incision in carpal tunnel syndrome surgery. PATIENTS AND METHODS: Carpal tunnel release with a 3 cm limited palmar incision was performed on 91 hands in 83 patients. Patients were evaluated with Boston Carpal Tunnel Questionnaire, grip strength and pinch strength measurements, Semmes-Weinstein Monofilament test and two-point discrimination tests preoperatively, and at postoperative 3rd and 6th months. The pre- and postoperative mean values for these assessment criteria were statistically analyzed by paired samples t-test. The symptoms, physical findings, electroneuromyography carpal tunnel syndrome severity scores of the patients were evaluated using descriptive statistical analyses. RESULTS: At postoperative evaluation, there was a statistically significant increase in Boston Carpal Tunnel Questionnaire scores, grip and pinch strengths, and sensory tests results of the patients when compared with preoperative values. No complications other than pillar pain were encountered. CONCLUSION: Carpal tunnel release with a 3 cm limited incision technique appears to be effective when compared with classical open, endoscopic and mini incision techniques. The rate of complications is lower than that of these techniques. In conclusion, a 3 cm limited incision is both effective and safe in carpal tunnel release.

Over-the-top knot placement technique enhances tensile stability of tendon repairs.

BACKGROUND: Currently a major concern for the surgical treatment of Achilles tendon rupture repairs is the creation of stable enough fixation to allow early range of motion. It was documented that the weakest point in a suture loop is the knot. Thus, we hypothesized that moving the knot away from the repair junction (over-the-top Krackow technique) would increase the strength of the repair. MATERIALS AND METHODS: Transected bovine tendons were repaired by the traditional Krackow and over-the-top Krackow techniques using four suture materials (Fiberwire Nos. 5 and 2, Ethibond Nos. 5 and 2). Tendons were cyclically tested at incremental loads beginning from 50 N until 5-mm gap formation. Then all tendons were loaded to failure. The number of cycles to 5-mm gapping, ultimate failure loads and knot slip were compared using t-test and Mann-Whitney tests (with Tukey corrections for multiple comparisons). RESULTS: Mean number of cycles to 5-mm gapping did not reveal significant differences (p = 0.113) between repair groups. Mean failure load of tendons repaired by over-the-top Krackow technique were significantly higher (p < 0.0001) for all four paired groups than tendons repaired by traditional Krackow technique. Ethibond No. 5, No. 2, and Fiberwire No. 2 suture repairs with over-the-top configuration did not reveal any knot slip. CONCLUSION: Over-the-top Krackow technique increases the ultimate failure load of repaired tendons. But 5-mm gapping resistivity was not enhanced either by the technique or the suture material. CLINICAL RELEVANCE: The knot itself is a stress-riser in the suture loop so we suggest that freeing it from tension by our modificiation may achieve more durable repairs.

Risk of osteonecrosis of the femoral condyle after arthroscopic chondroplasty using radiofrequency: a prospective clinical series.

Radiofrequency (RF) energy can be used for treatment of intraarticular pathologies in knee joint. RF energy was found to be superior to mechanical techniques in smoothening the articular surface (chondroplasty), shortening the operation time and reducing the blood loss. As RF produces thermal energy it has been reported to be responsible for the postoperative osteonecrosis however, there is no clinical evidence in the literature supporting that RF causes osteonecrosis. The current study searches for an answer whether surgical arthroscopic modalities using RF energy causes osteonecrosis. We hypothesize in the presented study that chondroplasty with RF has no effect on increasing the incidence of osteonecrosis in knee joint. In a prospective clinical trial, arthroscopic chondroplasty was performed in 50 patients with degenerative changes of the articular cartilage, stage II and III according to Outerbridge. To be included in the study, the patients had to meet the following criteria: (1) Preoperative MRI and plain film radiographs showing no evidence of osteonecrosis. (2) Patients had to be symptomatic for at least 6 weeks before the preoperative MRI. (3) Arthroscopically confirmed stage II or III. Preoperative MRI was taken in all patients. For chondral lesions bipolar RF energy system (VAPR-DePuy Mitek, Norwood, USA) was used. The patients were examined at the end of the sixth month and we performed MRI. Fifty patients with an average of age 45.54 (between 18 and 64) (SD, 10.63). During arthroscopy, together with chondropathy 22 patients pure medial meniscus tears, 7 patients medial and lateral meniscus tears, 7 patients pure lateral meniscus tears, 2 patients medial plica, and 3 patients synovial hypertrophy were detected. Among all 50 patients, osteonecrosis were detected at only 2 (4%) in the postoperative period. Until now it was not clear that RF energy causes osteonecrosis; however, according to this study if proper method is used, bipolar RF energy used for arthroscopic chondroplasty does not causes subchondral osteonecrosis.

Arthroscopy-assisted combined external and internal fixation of a pilon fracture of the tibia.

There are serious problems with existing methods of treating pilon fractures of the tibia caused by high-energy trauma. The method chosen to treat these fractures should not raise the risk of infection while effectively restoring the joint surface. We successfully treated a 42-year-old male patient with a pilon fracture caused by high-energy trauma using an arthroscopy-assisted unilateral external fixator and minimally invasive internal osteosynthesis. We used arthroscopy to reposition the fracture fragments and restore the joint surface. The fracture fragments were fixed with screws immediately after being repositioned. We believe that arthroscopy-assisted combined external and minimally invasive internal fixation is the treatment of choice for these fractures. We used external fixation to improve the fracture alignment, arthroscopy for restoring the joint surface, and minimally invasive screws to ensure fragment stability.

The relationship between Hill-Sachs lesion and recurrent anterior shoulder dislocation.

The relationship between the number of shoulder dislocations and the depth and percent of head involvement of the Hill-Sachs lesions was investigated in this study. Thirty patients with recurrent anterior dislocation of the shoulder were divided into three groups according to the numbers of dislocations they had presented: Group 1: 1 to 5 dislocations ; Group 2: 6 to 20; Group 3: over 20. The mean percentage of head involvement was 11.9% in the first group, 25.4% in the second group and 26% in the third group of patients with Hill-Sachs lesions. The average depth of the Hill-Sachs lesions was 4.14 mm in the first group, 5.13 mm in the second group and 4.38 mm in the third group. Based on these findings, it appears that there is a correlation between the number of dislocations and the extent and depth of the Hill-Sachs lesions. Surgical treatment should therefore be performed as early as possible in patients with recurrent anterior dislocation of the shoulder, in order to prevent progression of the Hill-Sachs lesion which can become by itself a cause of instability.

Second-look arthroscopy after arthroscopy-assisted treatment of tibial plateau fractures.

The only way to show the healing potential in hyaline cartilage after the treatment of tibial plateau fractures in humans is the second-look arthroscopy. Our aim is to examine the healing potential of the hyaline cartilage in tibial plateau fractures treated with arthroscopy-assisted surgery. We applied second-look arthroscopy to the 12 patients out of 52 who had tibial plateau fractures treated by arthroscopy-assisted surgery. The mean age was 41. The tibial plateau fractures were classified according to Schatzker classification. The period between the primary surgical treatment and second-look arthroscopy was on an average of 19 months. Step-off was detected in 3 out of 12 patients. Hyaline cartilage of nine patients who did not have step-off was found obviously on the fracture line. None of them had displacement. Three patients out of 12 were above 50 years old and the average follow-up period was 26 months. Grade II-III chondral defect was detected on the fracture line and femoral condyle in patients above 50 years. For patients below 50 years old, the follow-up period was 21 months and grade I-II chondral defect was detected on the fracture line and femoral condyle. Until now in literature, tibial plateau fractures have been evaluated clinically and radiologically, but in our cases we directly saw the lesion. Cartilage healing is limited in human beings. On the fracture line, cartilage defect continues, although anatomic reduction has been achieved. Moreover, if there is step-off, insufficient healing potential appears. Although we did not have enough cases, we can say that in tibial plateau fractures anatomic reduction is mandatory. Contrary to the common idea, step-off is not tolerated by hyaline cartilage.

Computerized tomography scout view for determining distal femoral resection angle in intramedullary instrumentation of total knee arthroplasty.

This study aims to investigate the results of distal femoral resection by determining the difference between mechanical and anatomical axes of femur using computerized tomography (CT) scout views in pre-operative planning of total knee arthroplasty. CT scout view of the lower extremities was taken before and after the operation in 16 patients undergoing total knee arthroplasty. Distal femoral resection was performed according to the previously determined ideal resection angle (IRA) using intramedullary instrumentation. At post-operative scanogram, femoral component deviation (FCD) was measured. The results were statistically analyzed. The average IRA was 6.95 (5-9) degrees. At post-operative measurements, the average FCD was 0.63 (0-3) degrees. CT scout films improve the accuracy in distal femoral resection and femoral component alignment.

Is there a safe area for the axillary nerve in the deltoid muscle? A cadaveric study.

BACKGROUND: Several authors have defined a variety of so-called safe zones for deltoid-splitting incisions. The first aim of the present study was to investigate the distance of the axillary nerve from the acromion and its relation to arm length. The second aim was to identify a safe area for the axillary nerve during surgical dissection of the deltoid muscle. METHODS: Twenty-four shoulders of embalmed adult cadavers were included in the study. The distance from the anterior edge of the acromion to the course of the axillary nerve was measured and was recorded as the anterior distance. The same measurement from the posterior edge of the acromion to the course of the axillary nerve was made and was recorded as the posterior distance for each limb. Correlation analysis was performed between the arm length and the anterior distance and the posterior distance for each limb. The ratios between arm length and the anterior and posterior distances were calculated for each case and were recorded as an anterior index and a posterior index. RESULTS: The average arm length was 30.40 cm. The average anterior distance was 6.08 cm, and the average posterior distance was 4.87 cm. There was a significant correlation between arm length and both anterior distance (r = 0.79, p < 0.001) and posterior distance (r = 0.61, p = 0.001). The axillary nerve was not found to lie at a constant distance from the acromion at every point along its course. The average anterior index was 0.20, and the average posterior index was 0.16. CONCLUSIONS: The present study describes a safe area above the axillary nerve that is quadrangular in shape, with the length of the lateral edges being dependent on the individual's arm length. Using this safe area should provide a safe exposure for the axillary nerve during shoulder operations.

Localized pigmented villonodular synovitis of the knee: acute onset in pregnancy.

A pregnant patient in the first trimester presented with acute onset knee pain and effusion. As the clinical status was mimicking septic arthritis, surgery was performed. Arthroscopy demonstrated a local synovial tumor and excision was performed with arthrotomy. Microscopic evaluation revealed localized pigmented villonodular synovitis. Due to the presence of necrosis and hematoma in the tumor, we hypothesize that, that torsion or bleeding of the tumor in the presence of physiological pregnancy- related metabolic changes might have been the cause of acute presentation.

Simultaneous bucket handle tear of both medial and lateral menisci of a knee with chronic anterior cruciate ligament deficiency.

Bucket handle meniscus tears constitute about 10% of all meniscal tears. Bucket handle tears of medial meniscus is three times more than lateral meniscus. Most of these tears are associated with anterior cruciate ligament (ACL) deficiency. Lateral meniscus lesions are more common with acute ACL deficiency, where medial meniscus lesions are more associated with chronic ACL deficiency. We identified bucket handle tears of each meniscus of a 30-year-old male patient while performing diagnostic arthroscopy during ACL reconstruction procedure. We present an ACL deficient knee with bucket handle tears of medial and lateral meniscus of the same knee and discuss the treatment.

Quadrilateral space syndrome caused by a humeral osteochondroma: a case report and review of literature.

Quadrilateral space syndrome (QSS) is a rare condition in which the posterior humeral circumflex artery and the axillary nerve are entrapped within the quadrilateral space. The main causes of the entrapment are abnormal fibrous bands and hypertrophy of the muscular boundaries. Many other space-occupying causes such as a glenoidal labral cyst or fracture hematoma have been reported in the literature. However, we could not find a report on classical QSS caused by an osteochondroma. The aim of this case report is to attract attention to an unusual etiology of shoulder pain, and to emphasize the importance of physical examination and x-ray imaging before performing more complex attempts for differential diagnosing.

Open repair of Bankart lesions using suture anchors in hard workers.

The surgical techniques applied to recurrent anterior dislocation of the shoulder, especially in hard working patients, must reconstruct a stable shoulder joint with a good range of motion, which will not re-dislocate, so the patients can return to their hardworking duties. The aim of this study was to evaluate the results of open Bankart repairs with suture anchors, in high-demand sportsmen and hard workers with recurrent anterior shoulder dislocation. Thirty shoulders of 29 patients were included in the study. All patients were active hard workers. A modified deltopectoral incision was used and Mitek GII Suture Anchors were implanted with 7-10 mm intervals into the bone-cartilage zone of the glenoid rim. Average follow-up time was 30 months (range, 22-38). Postoperative results were analysed according to the Rowe Scoring System. We obtained good and excellent results in 93.3% of cases. The open Bankart repair using suture anchors appeared in this study as a reliable technique for hard workers or physically high-demand patients.