The evolution of partial undercutting facetectomy in the treatment of lumbar spinal stenosis.

Decompression of lumbar spinal stenosis is the most common spinal surgery in those over 60 years of age. While this procedure has shown immediate and durable benefits, improvements in outcome have not changed significantly. Technical aspects of surgical decompression have evolved significantly. The recently introduced ultrasonic bone cutter allows a precise and safe peri-neural bone resection. The principles of preservation of stability, as described by Getty et al. have remained as relevant as when these were described 40 years ago.

Triple osteotomy for the correction of severe hallux valgus deformity: Patient reported outcomes and radiological evaluation.

BACKGROUND: Symptomatic Hallux valgus can be treated with metatarsal osteotomy combined with proximal phalangeal osteotomy, however this might not be sufficient to treat severe HV deformities. METHODS: Fifteen feet in eleven female patients treated with double first metatarsal and proximal phalanx osteotomies without lateral release were prospectively studied and outcome measures including radiological angles and validated patient reported outcome scores collected. RESULTS: Mean radiological follow up was 15 months and PROMs data 17 months. Mean hallux valgus and intermetatarsal angles were corrected from 45 to 24.7° and 18.7 to 7.4° respectively. There was an eight degree recurrence of hallux valgus angle. There was no wound problems, non-unions or evidence of avascular necrosis. The EQ-5D descriptive index showed a non-statistically significant improvement. All three elements of the MOxFQ score showed a statistically significant improvement: Forefoot pain (59-26.8), Walking and Stability (49.9-29.6) and Social Interaction (56.4-33.1) CONCLUSION: Triple osteotomy, without a lateral soft tissue release, leads to good radiological and functional outcomes in those with severe hallux valgus deformity. Patients need to be warned of the recovery time and potential for future metalwork removal. The risk of early recurrence suggests that a lateral release should be included in order to maintain a long lasting correction.

The Role of Arthroscopic Partial Meniscectomy in the Management of Degenerative Meniscus Tears: A Review of the Recent Literature.

BACKGROUND: The use of arthroscopic partial meniscectomy for middle aged to older adults with knee pain is one of the most common surgical procedures with approximately 150,000 knee arthroscopies being carried out in the United Kingdom each year, and about five times that number in the United States. Despite this, the procedure remains controversial. The aim of this paper is to provide a comprehensive review of the role of arthroscopic meniscectomy in patients with degenerative meniscus tears and suggest recommendations for clinical practice. METHODS: A thorough literature search was performed using available databases, including Pubmed, Medline, EMBASE and the Cochrane Library to cover important randomised control trials surrounding the use of arthroscopic partial meniscectomy. RESULTS: The majority of randomised control trials suggest that arthroscopic partial meniscectomy is not superior to conservative measures such as exercise programmes. Furthermore, one randomised control trial found that arthroscopic partial meniscectomy was not even superior to sham surgery. CONCLUSION: There is significant overtreatment of knee pain with arthroscopic partial meniscectomy when alternative, less invasive and less expensive treatment options are equally effective. First-line treatment of degenerative meniscus tears should be non-operative therapy focused on analgesia and physical therapy to provide pain relief as well as improve mechanical function of the knee joint. Arthroscopic partial meniscectomy should be considered as a last resort when extensive exercise programmes and physiotherapy have been tried and failed.

Spectral-envelope-group-delay models for transients.

Transient signals such as plosives in speech or Castanets in audio do not have a specific modulation or periodic structure in time domain. However, in the spectral domain they exhibit a prominent modulation structure, which is a direct consequence of their narrow time localization. Based on this observation, a spectral-domain AM-FM model for transients is proposed. The spectral AM-FM model is built starting from real spectral zero-crossings. The AM and FM correspond to the spectral envelope (SE) and group delay (GD), respectively. Taking into account the modulation structure and spectral continuity, a local polynomial regression technique is proposed to estimate the GD function from the real spectral zeros. The SE is estimated based on the phase function computed from the estimated GD. Since the GD estimation is parametric, the degree of smoothness can be controlled directly. Simulation results based on synthetic transient signals generated using a beta density function are presented to analyze the noise-robustness of the SEGD model. Three specific applications are considered: (1) SEGD based modeling of Castanet sounds; (2) appropriateness of the model for transient compression; and (3) determining glottal closure instants in speech using a short-time SEGD model of the linear prediction residue.