Four-year follow-up results of lumbar spine arthrodesis using the Bagby and Kuslich lumbar fusion cage.

STUDY DESIGN: This was a prospective multicenter clinical trial of a lumbar interbody fusion cage with a minimum of 4 years' follow-up. OBJECTIVES: To determine whether the early positive clinical results in fusions with lumbar cages, such as the Bagby and Kuslich (BAK) cage, are maintained beyond 2 years. SUMMARY OF BACKGROUND DATA: Threaded cages have been used increasingly for the treatment of symptomatic degenerative intervertebral disc disease. Concerns about the long-term clinical outcomes of this procedure have been posed, particularly regarding bony fusion viability, revision rates, potential adjacent level disease, and late complications. METHODS: The study cohort was a 196-patient subset from a prospective investigational device exemption. In addition to early postoperative examinations, these patients were examined biannually with a minimum of 4 years' follow-up. Patient outcome was assessed by a 6-point scale that evaluated pain relief, and functional improvement was determined by changes in activities of daily living. Fusion rates and return to work were determined. Complications and secondary operations were reported and categorized as non-device related or device related. RESULTS: The patient cohort with 4-year follow-up represented 25.6% of the original study population eligible at that time. Overall, the largest percentage of pain relief and functional improvements occurred by 3 months, and these improvements were maintained at each follow-up. Overall fusion rate was 91.7% and 95. 1% at 2 and 4 years, respectively. In this cohort, 39.5% of patients were working or were able to work within 3 months of surgery. After 4 years, 62.7% of patients were gainfully employed or able to work. The late-occurring complication rate in this cohort was 13.8% (27/196). Complications necessitating a second operation occurred in 8.7% (17/196), whereas reoperations that were deemed device related were performed in 3.1% (6/196). CONCLUSIONS: This study indicates that the early positive benefits of interbody fusion cage procedures are maintained through 4 years with acceptably low morbidity.

Tomography versus computed tomography for assessing step off in intraarticular distal radial fractures.

Computed tomography scans have supplanted conventional tomography for many applications and often are considered the imaging study of choice for assessing intraarticular distal radial fractures. Concern about cost containment in healthcare delivery prompts the question of whether the two studies provide comparable information and at what cost. Common intraarticular distal radial fractures were created in 12 lightly embalmed cadaveric specimens. The fractures were fixed with radiolucent Kirschner wires. Articular step off was measured with a caliper. Plain radiographs, computed tomography scans, and trispiral tomograms were obtained of each specimen. Maximal step off was measured blindly by two musculoskeletal radiologists and four hand surgeons. The radiographic measurements were compared with the actual step off and expressed as a positive or negative deviation from the actual value. There was no statistically significant difference between computed tomography scans and tomograms in predicting step off. In addition, the difference between actual and radiographic measurements was insignificant in tomogram readings and different in one of the computed tomography measurements. In the authors' institution, a tomogram costs $200, and a computed tomography scan costs $562. Trispiral tomography is more accurate and cost effective than computed tomography, and thus when available should be considered the imaging modality of choice for assessing articular step off in distal radius fractures.

The Bagby and Kuslich method of lumbar interbody fusion. History, techniques, and 2-year follow-up results of a United States prospective, multicenter trial.

STUDY DESIGN: A prospective, multicenter trial of the Bagby and Kuslich method of lumbar interbody stabilization for chronic discogenic low back pain, with follow-up evaluation at 3 months, 6 months, and yearly thereafter, with independent radiographic analysis. OBJECTIVES: To report the history of development, the surgical techniques, and results of the Bagby and Kuslich method when used to manage discogenic pain of the lumbar spine in humans. SUMMARY OF BACKGROUND DATA: Disabling chronic low back pain frequently is resistant to conservative management. The "Bagby Basket" effectively has fused the equine and baboon spine. The results of biomechanical and animal studies performed over the last 20 years have suggested that a similar but improved design--the Bagby and Kuslich device--would be useful in stabilizing the human spine. METHODS: From 1992 to 1995, 947 patients with chronic discogenic low back pain were treated by Bagby and Kuslich interbody fusion in a strict, multicenter, prospective clinical trial by using either the open anterior or open posterior approach. The study involved 42 surgeons at 19 medical centers. The authors of the current report analyzed the fusion rates, pain relief, functional status, and complications occurring in patients who underwent long-term follow-up observation. RESULTS: The Bagby and Kuslich method is safe and effective when compared with methods described in previous reports of posterior and anterior lumbar interbody arthrodesis performed by using bone graft alone. Fusion occurred in 91% of patients at 24 months after surgery, and pain was eliminated or reduced in 84%. Function was improved in 91%. There were no device-related deaths, cases of major paralyses, device failures, or deep infections. CONCLUSIONS: Carefully selected middle-aged patients with chronic low back pain secondary to degenerative disc disease can be treated effectively and safely by skilled surgeons using the Bagby and Kuslich device for one- and two-level interbody fusion.

MRI of the Stener lesion.

OBJECTIVE: To assess the utility of MR in detecting surgically induced Stener lesions (displaced thumb ulnar collateral ligaments) in cadaveric models. DESIGN: Six cadaver thumbs had ulnar collateral ligament (UCL) tears created surgically. MR examinations (2D STIR and 3D GRASS) were performed identically on all specimens both before displacement (non-Stener) and after displacement (Stener lesion) of the UCL. The MR images were then randomly numbered. Each image was evaluated separately in blinded fashion by four musculoskeletal radiologists for the presence or absence of a Stener lesion. Each radiologist reinterpreted the images after an interval of several days. The interpretation was based on previously published criteria for Stener lesion diagnosis by MR. RESULTS: The sensitivity of GRASS ranged from 0.17 to 0.67 with the most experienced reader scoring the lowest. The specificity of GRASS ranged from 0.33 to 1.0 (most experienced reader 0.67, 0.83). STIR had a sensitivity of 0.00-0.17 and a specificity of 0.53-0.83. The kappa values for inter- and intraobserver agreement were measured. The intraobserver kappa for GRASS was 0.27-0.75 (most experienced reader 0.75). CONCLUSIONS: 2D imaging is probably inadequate for the evaluation of Stener lesions. The most likely reason is that the STIR slice thickness of 3 mm limits resolution of small UCLs. The poor sensitivity and specificity of GRASS as well as poor interobserver agreement suggest that MR may not be sufficiently accurate for Stener lesion evaluation.

Acceleration of ventricular tachycardia following propofol in a patient with heterotopic cardiac transplant. Cardioversion of ventricular tachycardia in the native heart.

A 52-year-old Caucasian male underwent heterotopic cardiac transplant and subsequently developed a ventricular tachycardia in his native heart. The arrhythmia was successfully treated by cardioversion, despite an increased rate associated with induction of anaesthesia with propofol. The method of synchronised cardioversion is described and a possible hypothesis for the acceleration of ventricular tachycardia following induction is discussed.