Comparison of the history and physical examination for hip osteoarthritis and lumbar spinal stenosis.

BACKGROUND: Leg pain associated with walking is sometimes incorrectly attributed to hip osteoarthritis (OA) or lumbar spinal stenosis (LSS). PURPOSE: This study compared physicians' values of signs and symptoms for diagnosing and differentiating hip OA and LSS to their clinical utility. STUDY DESIGN/SETTING: Musculoskeletal physicians were surveyed with online questionnaires. Patients were recruited from hip and spine specialty practices. PATIENT SAMPLE: Seventy-seven hip OA and 79 LSS patients. OUTCOME MEASURES: Signs and symptoms of hip OA and LSS. METHODS: Fifty-one of 66 invited musculoskeletal physicians completed online surveys about the values of 83 signs and symptoms for diagnosing hip OA and LSS. Of these, the most valued 32 symptoms and 13 physical examination items were applied to patients with symptomatic hip OA or LSS. Positive likelihood ratios (+LR) were calculated for each items' ability to differentiate hip OA from LSS, with a +LR>2 set as indicating usefulness for favoring either diagnosis. Positive LRs were compared with surveyed physicians' values for each test. RESULTS: All symptoms were reported by some patients with each diagnosis. Only 11 of 32 physician-valued symptoms were useful for discriminating hip OA from LSS. Eight symptoms favored hip OA over LSS: groin pain (+LR=4.9); knee pain (+LR=2.2); pain that decreased with continued walking (+LR=3.9); pain that occurs immediately with walking (+LR=2.4); pain that occurs immediately with standing (+LR=2.1); pain getting in/out of a car (+LR=3.3); pain with dressing the symptomatic leg (+LR=3.1); and difficulty reaching the foot of the symptomatic leg while dressing (+LR=2.3). Three symptoms favored LSS over hip OA: pain below the knee (+LR=2.3); leg tingling and/or numbness (+LR=2.7); and some pain in both legs (+LR=2.5). Notable symptoms that did not discriminate hip OA from LSS included: pain is less while pushing a shopping cart (+LR=1.0); back pain (+LR=1.1); weakness and/or heaviness of leg (+LR=1.1); buttocks pain (+LR=1.2); poor balance or unsteadiness (+LR=1.2); pain that increased with weight-bearing on the painful leg (+LR=1.3), and step to gait on stairs (+LR=1.7). Consistent with physicians' expectations, 7 of 13 physical examination items strongly favored hip OA over LSS: limited weight-bearing on painful leg when standing (+LR=10); observed limp (+LR=9); and painful and restricted range-of-motion with any of five hip maneuvers (+LR range 21-99). Four of five tested neurological deficits (+LR range 3-8) favored the diagnosis of LSS over hip OA. CONCLUSIONS: There is substantial crossover of symptoms between hip OA and LSS, with some physician-valued symptoms useful for differentiating these disorders whereas others were not. Physicians recognize the value of the examination of gait, the hip, and lower extremity neurological function for differentiating hip OA from LSS. These tests should be routinely performed on all patients for which either diagnosis is considered. Awareness of these findings might reduce diagnostic errors.

Adjacent segment degeneration following ProDisc-C total disc replacement (TDR) and anterior cervical discectomy and fusion (ACDF): does surgeon bias effect radiographic interpretation?

PURPOSE: Many investigators have reported the financial conflicts of interest (COI), which could result in potential bias in the reporting of outcomes for patients undergoing total disc replacement (TDR) rather than anterior cervical discectomy and fusion (ACDF). This bias may be subconsciously introduced by the investigator in a non-blinded radiographic review. The purpose of this study was to determine if bias was present when a group of spine specialists rated adjacent segment degeneration (ASD) following cervical TDR or ACDF. METHODS: Potential bias in the assessment of ASD was evaluated through the reviews of cervical radiographs (pre- and 6 years post-operative) from patients participating in the ProDisc-C FDA trial (ProDisc-C IDE #G030059). The index level was blinded on all radiographs during the first review, but unblinded in the second. Five reviewers (a radiologist, two non-TDR surgeons, and two TDR surgeons), two of whom had a COI with the ProDisc-C trial sponsor, assessed ASD on a three point scale: yes, no, or unable to assess. Intra- and inter-rater reliabilities between all raters were assessed by the Kappa statistic. RESULTS: The intra-rater reliability between reviews was substantial, indicating little to no bias in assessing ASD development/progression. The Kappa statistics were 0.580 and 0.644 for the TDR surgeons (p < 0.0001), 0.718 and 0.572 for the non-TDR surgeons (p < 0.0001), and 0.642 for the radiologist (p < 0.0001). Inter-rater reliability for the blinded review ranged from 0.316 to 0.607 (p < 0.0001) and from 0.221 to 0.644 (p < 0.0001) for the unblinded review. CONCLUSIONS: The knowledge of the surgical procedure performed did not bias the assessment of ASD.

A RCT comparing 7-year clinical outcomes of one level symptomatic cervical disc disease (SCDD) following ProDisc-C total disc arthroplasty (TDA) versus anterior cervical discectomy and fusion (ACDF).

PURPOSE: The objective of this trial was to compare the safety and efficacy of TDA using the ProDisc-C implant to ACDF in patients with single-level SCDD between C3 and C7. METHODS: We report on the single-site results from a larger multicenter trial of 13 sites using an approved US Food and Drug Administration protocol (prospective, randomized controlled non-inferiority design). Patients were randomized one-to-one to either the ProDisc-C device or ACDF. All enrollees were evaluated pre- and post-operatively at regular intervals through month 84. Visual Analog Scale (VAS) for neck and arm pain/intensity, Neck Disability Index (NDI), Short-Form 36 (SF-36), and satisfaction were assessed. RESULTS: Twenty-two patients were randomized to each arm of the study. Nineteen additional patients received the ProDisc-C via continued access. NDI improved with the ProDisc-C more than with ACDF. Total range of motion was maintained with the ProDisc-C, but diminished with ACDF. Neck and arm pain improved more in the ProDisc-C than ACDF group. Patient satisfaction remained higher in the ProDisc-C group at 7 years. SF-36 scores were higher in the TDA group than ACDF group at 7 years; the difference was not clinically significant. Six additional operations (two at the same level; four at an adjacent level) were performed in the ACDF, but none in the ProDisc-C group. CONCLUSIONS: The ProDisc-C implant appears to be safe and effective for the treatment of SCDD. Patients with the implant retained motion at the involved segment and had a lower reoperation rate than those with an ACDF.

Mimickers of lumbar radiculopathy.

Orthopaedic surgeons frequently treat patients who report pain that radiates from the back into the lower extremity. Although the most common etiology is either a herniated disk or spinal stenosis, a myriad of pathologies can mimic the symptoms of radiculopathy, resulting in differences in the clinical presentation and the workup. Therefore, the clinician must be able to distinguish the signs and symptoms of lumbar radiculopathy from pathologies that may have a similar presentation. Being cognizant of these other possible conditions enables the physician to consider a breadth of alternative diagnoses when a patient presents with radiating lower extremity pain.

Adjacent segment disc pressures following two-level cervical disc replacement versus simulated anterior cervical fusion.

Anterior cervical fusion (ACF) has been shown to alter the biomechanics of adjacent segments of the cervical spine. The goal of total disc replacement is to address pathology at a given disc with minimal disruption of the operated or adjacent segments. This study compares the pressure within discs adjacent to either a two-level simulated ACDF or a two-level total disc replacement with the ProDisc-C. A special automated motion testing apparatus was constructed. Four fresh cadaveric cervical spine specimens were affixed to the test stand and tested in flexion and extension under specific loads. Intradiscal, miniature strain-gauge-based transducers were placed in the discs above and below the "treated" levels. The specimens were then tested in flexion and extension. Pressure and overall angular displacement were measured. In the most extreme and highest quality specimen the difference at C3/C4 registered 800 kPa and the difference at C6/C7 registered 50 kPa. This same quality specimen treated with the ProDisc reached a flexion angle at much lower moments, 24.3 degrees at 5 N-m, when compared to the the SACF 12.2 degrees at 8.6 N-m. Therefore, the moment needed to achieve 15 degrees of flexion with the SACF treatment was 5.5 N-m and the ProDisc treatment was only 2.9 N-m. This initial data would indicate that adjacent level discs experience substantially lower pressure after two-level disc replacement when compared to two-level SACF. Additional testing to further support these observations is ongoing.