William Yeo

Clinical and Radiological Outcomes of Minimally Invasive Versus Open Transforaminal Lumbar Interbody Fusion

Study Design. Prospective study. Objective. Comparison of clinical and radiologic outcomes of minimally invasive (MIS) versus Open transforaminal lumbar interbody fusion (TLIF). Summary of Background Data. Open TLIF has been performed for many years with good results. MIS TLIF techniques have recently been introduced with the aim of smaller wounds and faster recovery. Methods. From 2004–2006, 29 MIS TLIF were matched paired with 29 Open TLIF. Patient demographics and operative data were collected. Clinical assessment in terms of North American Spine Society, Oswestry Disability Index, Short Form-36, and Visual Analogue scores were performed before surgery, 6 months and 2 years after surgery. Fusion rates based on Bridwell grading were assessed at 2 years. Results. The mean age for MIS and Open procedures were 54.1 and 52.5 years, respectively. There were 24 females and 5 males in both groups. Fluoroscopic time (MIS: 105.5 seconds, Open: 35.2 seconds, P < 0.05) and operative time (MIS: 216.4 minutes, Open: 170.5 minutes, P < 0.05) were longer in MIS cases. There was less blood loss in MIS (150 mL) versus Open (681 mL) procedures (P < 0.05). The total morphine used for MIS cases (17.4 mg) was less compared to Open (35.7 mg, P < 0.05). MIS (4 days) patients have shorter hospitalization compared to Open (6.7 days, P < 0.05). Both MIS and Open groups showed significant improvement in Oswestry Disability Index (P < 0.05), back pain and lower limb symptoms (North American Spine Society and Visual Analogue scores, P < 0.05), and Quality of Life scores (Short Form-36, P < 0.05) at 6 months and 2 years, but there was no significant difference between the 2 groups. Eighty percent of MIS and 86.7% of Open TLIF levels achieved grade 1 fusion (P > 0.05). Conclusion. MIS TLIF has similar good long-term clinical outcomes and high fusion rates of Open TLIF with the additional benefits of less initial postoperative pain, early rehabilitation, shorter hospitalization, and fewer complications.

Five-year outcomes of minimally invasive versus open transforaminal lumbar interbody fusion: a matched-pair comparison study.

Study Design. Retrospective analysis of prospectively collected data. Objective. To compare midterm clinical and radiological outcomes of minimally invasive surgery (MIS) versus open transforaminal lumbar interbody fusion (TLIF). Summary of Background Data. Open TLIF is a proven technique to achieve fusion in symptomatic spinal deformities and instabilities. The possible advantages of MIS TLIF include reduced blood loss, less pain, and shorter hospitalization. To date, there is no published data comparing their midterm outcomes. Methods. From 2004–2007, 40 cases of open TLIF were matched paired with 40 cases of MIS TLIF for age, sex, body mass index, and the levels on which the spine was operated. Oswestry Disability Index, neurogenic symptom score, the 36-Item Short Form Health Survey, and visual analogue scale scores for back and leg pain were obtained before surgery, 6 months, 2 years, and 5 years after surgery. Fusion rates were assessed using Bridwell classification. Results. Fluoroscopic time (MIS: 55.2 s, open: 16.4 s, P < 0.001) was longer in MIS cases. Operative time (MIS: 185 min, open: 166 min, P = 0.085) was not significantly longer in MIS cases. MIS had less blood loss (127 mL) versus open (405 mL, P < 0.001) procedures. Morphine use for MIS cases (8.5 mg) was less compared with open (24.2 mg, P = 0.006). Patients who underwent MIS (1.5 d) ambulated earlier than those who underwent open fusion (3 d, P < 0.001). Patients who underwent MIS (3.6 d) had shorter hospitalization than those who underwent open fusion (5.9 d, P < 0.001). Both groups showed significant improvement in Oswestry Disability Index, neurogenic symptom score, back and leg pain, SF-36 scores at 6 months until 5 years with no significant differences between them. Grade 1 fusion was achieved in 97.5% of both groups at 5 years. The overall complication rate was 20% for the open group and 15% for MIS group (P = 0.774), including 4 cases of adjacent segment disease for each group. Conclusion. MIS TLIF is comparable with open TLIF in terms of midterm clinical outcomes and fusion rates with the additional benefits of less initial postoperative pain, less blood loss, earlier rehabilitation, and shorter hospitalization. Level of Evidence: 3

A proposed set of metrics for standardized outcome reporting in the management of low back pain

Background and purpose — Outcome measurement has been shown to improve performance in several fields of healthcare. This understanding has driven a growing interest in value-based healthcare, where value is defined as outcomes achieved per money spent. While low back pain (LBP) constitutes an enormous burden of disease, no universal set of metrics has yet been accepted to measure and compare outcomes. Here, we aim to define such a set. Patients and methods — An international group of 22 specialists in several disciplines of spine care was assembled to review literature and select LBP outcome metrics through a 6-round modified Delphi process. The scope of the outcome set was degenerative lumbar conditions. Results — Patient-reported metrics include numerical pain scales, lumbar-related function using the Oswestry disability index, health-related quality of life using the EQ-5D-3L questionnaire, and questions assessing work status and analgesic use. Specific common and serious complications are included. Recommended follow-up intervals include 6, 12, and 24 months after initiating treatment, with optional follow-up at 3 months and 5 years. Metrics for risk stratification are selected based on pre-existing tools. Interpretation — The outcome measures recommended here are structured around specific etiologies of LBP, span a patient’s entire cycle of care, and allow for risk adjustment. Thus, when implemented, this set can be expected to facilitate meaningful comparisons and ultimately provide a continuous feedback loop, enabling ongoing improvements in quality of care. Much work lies ahead in implementation, revision, and validation of this set, but it is an essential first step toward establishing a community of LBP providers focused on maximizing the value of the care we deliver.

Surgically treated cervical myelopathy: a functional outcome comparison study between multilevel anterior cervical decompression fusion with instrumentation and posterior laminoplasty

BACKGROUND CONTEXT Multilevel cervical myelopathy can be treated with anterior cervical discectomy and fusion (ACDF) or corpectomy via the anterior approach and laminoplasty via the posterior approach. Till date, there is no proven superior approach. PURPOSE To elucidate any potential advantage of one approach over the other with regard to clinical midterm outcomes in this study. STUDY DESIGN A prospective, 2-year follow-up of patients with cervical myelopathy treated with multilevel anterior cervical decompression fusion and plating and posterior laminoplasty. PATIENT SAMPLE In total, 116 patients were studied. Sixty-four patients underwent ACDF two levels and above or anterior cervical corpectomy and fusion one level and above. Fifty-two patients underwent posterior cervical surgery (laminoplasty C3-C6 and C3-C7). OUTCOME MEASURES Self-report measures: Japan Orthopedic Association (JOA) score, JOA recovery rate, visual analog scale for neck pain (VASNP), neck disability index (NDI), and American Academy of Orthopaedic Surgeons (AAOS) neurogenic symptom score (AAOS-NSS). Physiologic measures: range of motion (ROM) flexion and extension of neck. Functional measures: short-form 36 (SF-36) score comprising physical functioning, physical role function, bodily pain, general health, vitality, social role function, emotional role function, and mental health scales. METHODS Comparison of the JOA scores, JOA recovery rates, NDI scores, SF-36 scores, VASNP, and ROM preoperatively to 2 years. Chi-square and two-sided Student t tests were used to analyze the variables. RESULTS Posterior surgery took an hour shorter (p<.05) and had better improvement in JOA scores at early follow-up of 6 months (p=.025). Anterior surgery group had better improvement of NDI scores at early follow-up of 6 months (p=.024) and was associated with less blood loss intraoperatively compared with posterior surgery. There was no statistical difference between the two groups for JOA scores, JOA recovery rates, SF-36 quality-of-life scores, NDI, AAOS-NSS, VAS neck pain, and ROM at 2 years. Complications were higher for anterior surgery group: two hematoma postoperation, one vocal cord paresis, and one new onset C6/C7 dermatome numbness versus one dura leak in posterior surgery group. CONCLUSIONS Our study showed that patients with multilevel disease treated with laminoplasty do well and compare favorably with patients treated with an anterior approach. Notably, posterior surgery was associated with shorter operating time, better improvement in JOA scores at 6 months, and a tendency toward lesser complications. Posterior surgery was not associated with increased neck disability and neck pain at 2 years. Anterior surgery had better NDI improvement at early follow-up. There is a need for a larger study that is prospectively randomized with long-term follow-up before we can confidently advocate one approach over the other in the management of cervical myelopathy.

The nature of the loss of strength and dexterity in the upper limb following stroke

Abstract People who had suffered a stroke within the previous two years were tested for strength, dexterity and the ability to generate fast movements of their affected elbow and compared to age-matched controls. Strength was measured via the joint torque generated during a maximal isometric contraction of the elbow flexors and extensors. Dexterity was assessed separately from strength by a tracking task that required skilled interaction of elbow joint flexors and extensors at two speeds — slow and fast. This task was set up so that very little strength was required to perform the task. Additionally, the ability to generate fast movements was measured by requiring subjects to flex and extend their elbow as fast as they could. Performance of the tracking task deteriorated at the faster speed in all subjects, however, this effect was more pronounced following stroke. In the stroke subjects, strength was poorly correlated with dexterity. Generally, stroke subjects could and did move their elbows in flexion and extension faster than was required to follow the targets. Poor performance of the stroke subjects on the tracking task was, therefore, the result of poor muscle control — a separate entity from strength. The results of this study indicate that weakness and loss of dexterity following stroke are separate problems, both of which may contribute to the slowness of movement seen in the clinic.

Intermediate Results of the Prestige LP Cervical Disc Replacement: Clinical and Radiological Analysis With Minimum Two-Year Follow-up.

Study Design. Prospective study. Objective. Present results of Prestige LP artificial cervical disc replacement (ADR). Summary of Background Data. Motion preservation with ADR can potentially reduce adjacent segment degeneration. Methods. Forty patients with 59 Prestige LP ADR were analyzed. Cervical range of motion, Neck Disability Index, Visual Analogue, Short Form-36, Modified American Academy of Orthopedic Surgeons, and Japanese Orthopedic Association scores and radiographs were evaluated. Clinical results were compared with anterior cervical discectomy and fusion. Results. There were 21 females and 19 males. Mean age was 43.9 years. Mean follow-up was 2.9 years. Of the patients, 62.5% had single level replacement-mainly C56 level (56%); 52.5% had myelopathy and 47.5% radiculopathy; 50% of neural compression was due to herniated disc, 45% due to spondylosis, and 5% due to both. There was significant improvement in the American Academy of Orthopedic Surgeons and Visual Analogue scores (P < 0.05) at 6 months and 2 years. There was significant improvement in the Neck Disability Index from a mean of 42.2 preoperation to 16.4 at 6 months and 15.2 at 2 years (P < 0.05). The mean Japanese Orthopedic Association score improved significantly from 14.7 preoperation to 15.7 at 6 months and 15.6 at 2 years (P < 0.05). There was significant improvement in all aspects of the Short Form-36 scores except general health (P < 0.05) at 6 months and 2 years. There was no significant difference in the clinical outcomes between ADR and anterior cervical discectomy and fusion. Segmental alignment (mean 8°, 14°, and 13° lordotic at preoperation, 6 months, and 2 years postoperation, respectively) and global alignment (mean 15.7°, 16.2°, and 17.3° lordotic at preoperation, 6 months, and 2 years postoperation, respectively) were maintained. Dynamic radiographs showed significant segmental motion with a 6 months mean motion of 11.1° and a 2-year mean motion of 13.9° (P < 0.05). Conclusion. Prestige LP ADR showed significant improvement in clinical outcomes at 2 years. It restores segmental lordosis and preserves segmental motion up to 2 years postoperation.

Learning curve of a complex surgical technique: minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

Study Design: Prospective cohort study. Objective: This study aimed to evaluate the learning curve of minimally invasive transforaminal lumbar interbody fusion (MIS TLIF). Summary of Background Data: Very few studies have evaluated the learning curve of this technically demanding surgery. We intend to evaluate the learning curve of MIS TLIF with a larger sample size and assess surgical competence based not only on operative time but with perioperative variables, clinical and radiologic outcomes, incidence of complications, and patient satisfaction. Materials and Methods: From 2005 to 2009, the first 90 single-level MIS TLIF, which utilized a consistent technique and spinal instrumentation, performed by a single surgeon at our tertiary institution were studied. Variables studied included operative time, perioperative variables, clinical (Visual Analogue Scores for back and leg pain, Oswestry Disability Index, North American Spine Society Scores for neurogenic symptoms) and radiologic outcomes, incidence of complications and patient rating of expectation met, and the overall result of surgery. Results: The asymptote of the surgeon’s learning curve for MIS TLIF was achieved at the 44th case. Comparing the early group of 44 patients to the latter 46, the demographics were similar. For operative parameters, only 3 variables showed differences between the 2 groups: mean operative duration, fluoroscopy duration, and usage of patient-controlled analgesia. At the final follow-up, for clinical outcome parameters, the 2 groups were different in 3 parameters: VAS scores for back, leg pain, and neurogenic symptom scores. For radiologic outcome, both groups showed similar good fusion rates. For complications, none of the MIS TLIF cases were converted to open TLIF intraoperatively. In the early group, there were 3 complications: 1 incidental durotomy and 2 asymptomatic cage migrations; and in the latter group, there was 1 asymptomatic cage migration. Conclusions: In our study, technical proficiency in MIS TLIF was achieved after 44 surgeries, and the latter patients benefited from shorter operative duration and radiation, less pain, and more relief in their back, leg, and neurogenic symptoms.

Percutaneous endoscopic discectomy: clinical results and how it affects the quality of life.

Study Design Prospective study Objective To determine the clinical outcomes and the effect on quality of life of patients with endoscopic discectomy. Summary of Background Data Percutaneous endoscopic discectomy is a relatively new technique. Very few studies have reported the clinical outcome of percutaneous endoscopic discectomy in terms of quality of life and return to the work. Method Fifty-five patients with percutaneous endoscopic discectomy performed from the year 2002 to 2006 had their clinical outcomes reviewed in terms of the North American Spine Score (NASS), Medical Outcomes Study Short Form-36 (SF-36) scores and Pain Visual Analog Scale (VAS) and return to the work. Results The mean age was 35.6 years, the mean operative time was 60 minutes and the mean length of follow-up was 3 years. The mean hospital stay for endoscopic discectomy was 17 hours. There was statistical difference in the reduction of severity of back pain and lower-limb symptoms (NASS and VAS, P<0.05) at 6 months and 2 years. There was significant improvement in all aspects of the quality of life (SF-36, P<0.05) scores except for general health at 6 months and 2 years postoperation. The improvement in the SF-36 quality of life parameters correlated with the improvement in the NASS back disability and neurogenic symptoms and the VAS leg and back pain scores. The recurrence rate was 5% (3 patients). The 5% patients (3 patients) subsequently underwent lumbar fusion for persistent back pain. All patients returned to their previous occupation after surgery at a mean time of 24 days. Conclusions Endoscopic discectomy is associated with improvement in back pain and lower-limb symptoms postoperation which translates to improvement in quality of life. It has the advantage that it can be performed on a day case basis with shorter length of hospitalization and early return to work thus improving quality of life earlier.

Predicting discharge outcomes after total knee replacement using the Risk Assessment and Predictor Tool

OBJECTIVE To explore the use of the Risk Assessment and Predictor Tool (RAPT) as a pre-operative tool to predict postoperative discharge destination and length of stay for patients undergoing total knee replacement (TKR) in Singapore. PARTICIPANTS AND SETTING A cohort of 569 patients undergoing primary TKR at the Singapore General Hospital were recruited prospectively from November 2009 to June 2010. INTERVENTION All patients completed a modified RAPT questionnaire pre-operatively, and underwent standard clinical pathway guidelines for TKR throughout the study. MAIN OUTCOME MEASURES Actual discharge destination (ADDest) and length of stay (LOS). DESIGN Total RAPT score and preferred discharge destination (PDD) were recorded pre-operatively, while ADDest and LOS were obtained immediately after discharge. Multivariable logistic regression and multivariable regression analysis were used to determine whether the RAPT items and score could predict the discharge outcomes. RESULTS Total RAPT score was a significant predictor of LOS for patients following TKR (R=0.24, P<0.001); the higher the RAPT score, the longer the LOS. Total RAPT score was also a significant predictor of actual discharge to home [odds ratio (OR) 2.32, 95% confidence interval (CI) 1.11 to 4.85]. PDD was a significant predictor for LOS (R=0.22, P<0.001) and ADDest (R=0.33, P<0.001). Patients who chose to be discharged home were more likely to be directly discharged home (OR 9.79, 95% CI 5.07 to 18.89, P<0.001). CONCLUSION Total RAPT score and PDD were significant predictors of ADDest and LOS for patients following TKR in Singapore. The ability to predict discharge outcomes following TKR could assist caregivers, healthcare professionals and administrators in optimising care and resource allocations for patients.

Comparison of the responsiveness of the SF-36, the Oxford Knee Score, and the Knee Society Clinical Rating System in patients undergoing total knee replacement

ObjectivesTo compare the responsiveness of the Knee Society (KS) Clinical Rating System, the general health status measure Short Form 36 (SF-36), and both the raw and Rasch-based scores of the condition-specific Oxford Knee Score (OKS) in patients undergoing total knee replacement (TKR)MethodsData were prospectively collected as part of routine care from adult patients who underwent TKR between 2001 and 2006. OKS data fit the Rasch partial credit model after removing items regarding limping and kneeling. Responsiveness was assessed using effect size (ES), standardised response mean (SRM), and relative validity (RV).ResultsAmong 702 patients with complete data at baseline and two follow-ups, the pain subscale of the KS (KS-P), raw-OKS, and Rasch-OKS consistently had higher levels of responsiveness than all eight SF-36 and the other KS subscales. At 6-month follow-up, Rasch-OKS had the largest ES and KS-P had the largest SRM (2.7 and 2.0, respectively). When compared to raw-OKS, the RVs of KS-P, Rasch-OKS, SF-36 bodily pain, and SF-36 physical functioning were 1.1, 0.66, 0.49, and 0.36, respectively. A similar ordering of responsiveness was observed at 24-month follow-up.ConclusionThe OKS and KS-P are more responsive than most SF-36 subscales in TKR patients. Raw-OKS and Rasch-OKS have comparable responsiveness. Different responsiveness indices may give different results.