Evidence based medicine is the practice of solving the clinical problems in one's practice by judicious and systematic use of the medical literature. This includes framing questions rightly and searching the right kind of literature. Thereafter, the available evidence needs to be evaluated for the validity, strength and effect size. Finally, the results are examined for applicability to the current problem which requires a detailed knowledge of the clinical setting, patient profile and the issues related to cost and harm. The present communication deals with these issues in a step-wise manner in order to stimulate readers to practise this important art.

The choice of outcome measure in orthopedic clinical research studies is paramount. The primary outcome measure for a study has several implications for the design and conduct of the study. These include: 1) sample size determination, 2) internal validity, 3) compliance and 4) cost. A thorough knowledge of outcome measures in orthopedic research is paramount to the conduct of a quality study. The decision to choose a continuous versus dichotomous outcome has important implications for sample size. However, regardless of the type of outcome, investigators should always use the most 'patient-important' outcome and limit bias in its determination.

Background: A large number of statistical fallacies occur in medical research literature. These are mostly inadvertent and occur due to lack of understanding of the statistical concepts and terminologies. Many researchers do not fully appreciate the consequence of such fallacies on the credibility of their report. Materials and Methods: This article provides a general review of the issues that could give rise to statistical fallacies with focus on orthopedic research. Some of this is based on real-life literature and some is based on the actual experiences of the author in dealing with medical research over the past three decades. The text is in teaching mode rather than research mode. Results: Statistical fallacies occur due to inadequate sample that is used for generalized conclusion; incomparable groups presented as comparable; mixing of two or more distinct groups that in fact require separate consideration; misuse of percentages, means and graphs; incomplete reporting that suppresses facts; ignoring reality and depending instead on oversimplification; forgetting baseline values that affect the outcome; misuse of computer packages and use of black-box approach; misuse of P -values that compromises conclusions; confusing correlation with cause-effect; and interpreting statistical significance as medical significance. Conclusion: Mere awareness of the situations where statistical fallacies can occur may be adequate for researchers to sit up and take note while trying to provide a credible report.

Objective: To compare the results of endoscopic carpal tunnel release (CTR) with open CTR in patients with idiopathic Carpal tunnel syndrome (CTS). Materials and Methods: Seventy-one patients with CTS were enrolled in a prospective randomized study from May 2003 to December 2005. All patients had clinical signs or symptoms and electro-diagnostic findings consistent with carpal tunnel syndrome and had not responded to nonoperative management. Sixty-one cases were available for follow-up. Endoscopic CTR was performed in 30 CTS patients and open CTR was performed in 31 wrists (30 patients). Various parameters were evaluated, including each patient's symptom amelioration, complications, operation time, time needed to resume normal lifestyle and the frequency of revision surgery. All the patients were followed up for six months. Results: During the initial months after surgery, the patients treated with the endoscopic method were better symptomatically and functionally. Local wound problems in terms of scarring or scar tenderness were significantly more pronounced in patients undergoing open CTR compared to patients undergoing endoscopic CTR. Average delay to return to normal activity was appreciably less in group undergoing endoscopic CTR. No significant difference was observed between the endoscopic CTR group and open CTR group in regard to symptom amelioration, electromyographic testing and complications at the end of six months. Conclusion: Short-term results were better with the endoscopic method as there was no scar tenderness. Results at six months were comparable in both groups.

Aim: To evaluate the functional and radiological outcome of primary total hip replacement (THR) using modular total hip system at 2-10 years follow-up. Materials and Methods: The cohort comprised 100 operated cases for total hip replacement using modular hip system, with an average follow-up of 6.02 years ranging from 2-10 years. In 61 cases cemented THR, in 36 cases hybrid and in three cases uncemented THR was done. Harris hip score was used for clinical evaluation. Osteolysis was recorded in three acetabular zones described by DeLee and Charnley and the seven femoral zones described by Gruen et al . Results: The average age at operation was 52.46±9.58 years. Mean follow-up duration was 6.02 years ranging from 2-10 years. Four patients died due to causes unrelated to surgery. At the last follow-up mean Harris Hip score was 83.5. Radiolucent lines were present in 39(39%) acetabular and 32 (32%) femoral components. Osteolysis was most common in Zone 7 of the femoral and Zone II and III of the acetabular component. Eight hips have been revised, five for aseptic loosening as proved by negative culture at revision and three hips for posttraumatic periprosthetic femoral fracture. One girdle stone resection was done for deep infection. Out of 96 hips available at latest follow-up, 87 primary arthroplasties were intact and functioning well. Conclusion: The results of our study support the continued use of the modular hip system. The acetabular loosening was more common than femoral in our study.

Background: Bone marrow is a source of osteoprogenitor cells that are key elements in the process of bone formation and fracture healing. The purpose of the study was to ascertain the osteogenic potential of autologous bone marrow grafting and its effectiveness in the management of delayed union and nonunion. Materials and Methods: Twenty-eight patients with delayed union and three with nonunion of fracture of the long bones were treated with this procedure. Of these 28 cases, two patients had fracture shaft femur, one had fracture shaft ulna and 25 patients had tibial shaft fractures. The average time duration between procedure and injury was 25 weeks (range 14-53 weeks). The bone marrow was aspirated from the anterior iliac crest and injected percutaneously at the fracture site. The procedure was carried out as an outpatient procedure. All but five cases required one injection of bone marrow. Results: Union was observed in 23 cases. The average time of healing after the procedure was 12 weeks (range 7-18 weeks). Conclusion: The technique of percutaneous autologous bone marrow injection provides a very safe, easy and reliable alternative to open bone grafting, especially for early intervention in fracture healing process.

Spinal dysraphism is a common congenital anomaly with many associated variants. One of the rarest associated findings is a full grown or rudimentary third limb, collectively called Tripagus. We present two cases of spinal dysraphism with rudimentary third limb arising from the ilium.

Primary spinal hydatid disease is rare and represents an uncommon but significant manifestation of hydatid disease. We report a case of primary intraspinal extradural hydatid cyst of the thoracic region causing spinal cord compression. The presenting symptoms were mostly atypical and the diagnosis was established preoperatively on the basis of magnetic resonance imaging. The patient underwent surgery resulting in complete recovery and is recurrence-free after 24 months follow-up.

Hemangioma of the median nerve presenting as acute carpal tunnel syndrome is unusual A-18- year old male presented with severe incapacitating pain of sudden onset of left forearm and hand after manual field work. There was swelling on volar aspect of forearm, with hyperalgesia in the median nerve distribution. The fingers and wrist were inmarked flexion and the patient did not allow wrist and finger extension. X-rays were within normal limits. An emergency volar carpal ligament release revealed, haematoma about 100 ml with numerous vessels encircling the median nerve. Histopathology of lesion turned out to be a cavernous hemangioma. Post operatively patient had full recovery.