Comparison of gait kinematics in total and unicondylar knee replacement surgery.

INTRODUCTION: This study is aimed to compare kinematic gait data of patients who have undergone total and unicondylar knee replacement. MATERIALS AND METHODS: This single-surgeon retrospective cohort study evaluated 13 patients with unilateral total knee arthroplasty (TKA) and 14 unicondylar knee arthroplasty (UKA). Gait analysis was carried out using a Vicon motion analysis system. The limits of knee flexion during stance phase, at heel strike and at loading response were measured. RESULTS: The total range of motion of the UKA knees was significantly greater than the TKA knees. UKA knees exhibited significantly greater knee extension during the stance phase than the TKA knees. Unlike TKA, UKA knees demonstrated improved knee flexion during the gait cycle when compared to the contralateral non-operated knee. The hips also demonstrated near normal hip flexion in UKA patients. Predictably, UKA knees had significantly greater varus compared with TKA in the coronal plane. Spatiotemporal variables demonstrated similar walking speed and step length to aid a fair comparison between knee replacement groups. CONCLUSIONS: The UKA knees moved more physiologically in the sagittal plane with a greater range of motion during gait. Despite having a stiff gait pattern, the patients undergoing TKA demonstrated a more neutral alignment in the coronal plane. Neither type of knee arthroplasty restored knee kinematics to those of the non-operated side.

Comparison of gait kinetics in total and unicondylar knee replacement surgery.

Introduction The aim of this study was to compare kinetical data from gait analysis of patients who have undergone total and uni-condylar knee replacement. Materials and methods Thirteen patients with unilateral total knee arthroplasty (TKA) and 13 unicondylar knee arthroplasty (UKA), were included, all performed by the same surgeon more than one year prior. The Vicon gait analysis system was used. Statistical power was calculated using SPSS. Results No significant difference was found in the spatiotemporal parameters of gait and survival years of the knee prosthesis between the two groups. The UKA group was found to have significantly larger moments than the TKA group in knee adduction on the operated side and knee flexion moment on the unoperated side during the loading phase. The maximum and minimum sagittal plane moments of the operated sides in the TKA group were significantly lower than the unoperated side. The difference was most significant at pre-swing. The maximum and minimum moments on the operated sides in the UKA group were significantly lower for the knee flexion and adduction moments when compared with the unoperated side and were most prevalent during the loading phase. Conclusions These results are relevant in terms of prosthesis wear. The TKA knees had smaller magnitude moments than the UKA knees in the sagittal and coronal planes. This could explain the higher revision rates for UKA. In both groups, the non-operated knees had significantly larger moments than the operated knees, which implies that after unilateral knee replacement of either type, the non-operated knee is being put under greater stress.

Efficacy of low-level laser therapy applied at acupuncture points in knee osteoarthritis: a randomised double-blind comparative trial.

OBJECTIVE: To evaluate the efficacy of low-level laser therapy (LLLT) applied to acupuncture points on the knee joint in combination with exercise and advice in patients with knee osteoarthritis. DESIGN: Randomised, double-blind, comparative clinical trial. PARTICIPANTS: Forty-nine patients with knee osteoarthritis were assigned at random into two groups: active laser group (n=26) and placebo laser group (n=23). INTERVENTION: Using a gallium aluminium arsenide laser device, patients received either active or placebo LLLT at five acupuncture points on the affected knee during nine sessions. OUTCOME MEASURES: Patients were assessed using a visual analogue scale (VAS) and the Saudi Knee Function Scale (SKFS) at baseline, the fifth treatment session, the last treatment session, 6 weeks post intervention and 6 months post intervention. RESULTS: VAS scores showed a significant improvement in the active laser group compared with the placebo laser group at 6 weeks post intervention [mean difference -1.3, 95% confidence interval (CI) of the difference -2.4 to -0.3; P=0.014] and 6 months post intervention (mean difference -1.8, 95% CI of the difference -3.0 to -0.7; P=0.003) using the independent samples test. SKFS scores also showed a significant improvement in the active laser group compared with the placebo laser group at the last treatment session (median difference -15, 95% CI of the difference -27 to -2; P=0.035) and 6 months post intervention (median difference -21, 95% CI of the difference -34 to -7; P=0.006) using the Mann-Whitney U test. CONCLUSIONS: The results demonstrate that short-term application of LLLT to specific acupuncture points in association with exercise and advice is effective in reducing pain and improving quality of life in patients with knee osteoarthritis.

Assessment of talipes equinovarus treated by Ponseti technique: three-year preliminary report.

BACKGROUND: The Ponseti method has become increasingly popular in the treatment of congenital talipes equinovarus (CTEV). Current methods of assessment focus on clinical, functional and radiological outcomes which are subjective and often difficult to repeat. However, integration of biomechanical evaluation can provide objective and quantifiable analysis. This study aims to evaluate the treatment outcome of CTEV patients on the basis of long-term clinical, functional and biomechanical assessment. METHODS: Following treatment, five children with CTEV were reviewed annually for the period 2008-2010. Clinical and functional outcomes were graded using parental questionnaires and clinical examination. Biomechanical parameters were evaluated using digital foot pressure studies. RESULTS: The study group recorded good clinical and functional outcomes. However, biomechanical studies have been able to identify subtle abnormalities that would be unapparent otherwise on clinical examination. CONCLUSIONS: It is recommended that biomechanical assessment be integrated into the overall evaluation of the outcome of CTEV after treatment.

Keller's arthroplasty in adults with hallux valgus and hallux rigidus.

BACKGROUND: The role of Keller's resection arthroplasty in the management of adult hallux valgus with hallux rigidus is debatable. There are no studies addressing this particular problem. METHODS: This study is a retrospective review of 32 patients (49 feet), conducted by an independent assessor. Subjective and objective criteria were used to assess the results of surgery. There were 30 women and 2 men with an average age at surgery of 62.5years. RESULTS: The results of surgery in terms of relief of pain, cosmesis and use of regular footwear were satisfactory. Excellent and good subjective results were obtained in 39% and 37% of cases respectively. Radiological analysis revealed decrease in the intermetatarsal and first metatarsophalangeal angle in a significant number of cases. Final results assessed by Vallier's modification of Bonney and MacNab criteria, revealed excellent to good results in 87% of feet. A significant number of complications were noted but there was no association between the occurrence of complications and the final result or the subjective functional grade. There was no association between the amount of resection of proximal phalanx and occurrence of metatarsalgia or the final outcome. CONCLUSION: The results of this study suggest that Keller's arthroplasty has a role in patients with adult hallux valgus associated with degenerative changes in the first metatarsophalangeal joint.

The influence of shoe sole's varying thickness on lower limb muscle activity.

BACKGROUND: The lateral ligament injury of the ankle is acknowledged to be the most common ankle injury sustained in sport. Increased peroneus longus muscle contraction in the shod population has already been documented. This study aimed to quantify the effect of shoe sole's varying thickness on peroneus longus muscle activity. METHODS: Electromyographic recordings of the peroneus longus muscle activity following unanticipated inversion of the foot from 0° to 20° in a two-footplate tilting platform were collected from 38 healthy participants. The four test conditions were: barefoot, standard shoe, and shoes with 2.5 cm and 5 cm sole adaptation respectively. RESULTS: Compared to the barefoot condition, there is an increase in the magnitude of muscle contraction on wearing shoes, which further increases with thickening shoe soles. The peroneus longus was responding earlier in the shod conditions when compared to the barefoot, although the results were variable within the three shod conditions. CONCLUSION: Footwear with increasing shoe sole thickness evokes a correspondingly stronger protective eversion response from the peroneus longus to counter the increasing moment at the ankle-subtalar joint complex following sudden foot inversion. Hence, fashion footwear with thicker sole is likely to increase the risk of lateral ligament injury of the ankle when such protective response is overwhelmed. Similarly, the clinicians need to be cautious regarding the amount of shoe raise that they could provide for patients with limb length discrepancy without any detrimental untoward side effects.

Harmful cleats of football boots: a biomechanical evaluation.

BACKGROUND: Football players wear boots of varying cleat designs with some preferring the bladed cleats while others opting for the conventional studded cleats. The current study compares biomechanically the boots with differing cleat designs and their effect on feet, if any. METHODS: Twenty-nine healthy male volunteers were recruited from amateur football teams. They were asked to perform three trials each of two activities: a straight run and a run cutting at a 60° angle wearing bladed and studded Adidas®-F series boots on artificial turf. Plantar pressure values were recorded using the Pedar®-X in-shoe pressure measuring device. Peak pressure and pressure-time integral were analysed over 11 clinically relevant areas under the foot. RESULTS: While the in-shoe pressure and pressure-time integral were higher under the medial half of the foot with studded boots, they were higher under the lateral half of the foot with the bladed design. CONCLUSIONS: The studded boots can be considered safer as the pressure distribution across the foot and the pattern of centre of pressure progression mimicked the normal motif, whereas the bladed boots could potentially be deemed relatively more harmful due to the unnatural increased loading under the lateral half of the foot, predisposing the foot to injuries.

Objective assessment of the alterations in wrist mobility with the fastrak(®) system following dorsal capsulodesis.

The treatment for scapholunate dissociation is challenging and its management is varied depending on type, severity and duration of injury, and surgeon's preferred technique. This study aimed to objectively assess the variations in the range and patterns of wrist movements using the Fastrak(®) system in patients having undergone Blatt's dorsal capsulodesis (BDC). The wrist movements were successively measured between the operated and unoperated wrists, while the patients performed set tasks. Seventeen patients agreed to participate in the study. Following BDC the mean flexion loss was 23° (range 10°-38°). However, functional tasks revealed that the BDC did not adversely affect the function of the operated wrist. This novel study demonstrates objectively the functional restrictions that patients are likely to experience postoperatively following BDC. It would be interesting to note the pattern of wrist motion using the Fastrak(®) system in various other clinical settings.

Differences in foot pressures between Caucasians and Indians.

BACKGROUND: Indians are the largest single ethnic minority group in the United Kingdom and form more than one million of the current population. No studies have investigated foot pressure differences between Caucasians and Indians. OBJECTIVE: The aim of our study was to investigate the in-shoe pressure differences in Caucasians and Indians using the Pedar(®)-m (Novel GmbH, Germany). METHODS: The study included 12 Caucasians and 21 Indians. Peak pressure (PP), contact area (CA), contact time (CT), pressure-time integral (PTI), force-time integral (FTI), instant of peak pressure (IPP), maximum force (MaxF) and mean force (MeanF) were recorded. RESULTS: Caucasians had higher significant PP compared to Indians under the heel (293 kPa vs. 251 kPa; P<0.001), 1st metatarsal head (294 kPa vs. 233 kPa; P=0.01), 2nd metatarsal head (266 kPa vs. 236 kPa; P=0.03), 3rd metatarsal head (254 kPa vs. 223 kPa; P=0.04), and the 5th metatarsal head (168 kPa vs. 133 kPa; P=0.04). There was no significant difference in the contact area between the two race groups. The PTI was statistically significantly higher in Caucasians in the region of the 1st metatarsal head (79 kPas vs. 62 kPas; P=0.03) and 5th metatarsal head (58 kPas vs. 44 kPas; P=0.03). There were no significant differences among CT, FTI, IPP, MaxF and MeanF among them. CONCLUSION: The PP under the heel, 1st, 2nd, 3rd and 5th metatarsal heads and the PTI under the 1st and 5th metatarsal heads in Caucasians is higher than in Indians. There is no difference in the CA.

Repeatability of the Pedar-X in-shoe pressure measuring system.

BACKGROUND: The Pedar-X is one of the newer versions of in-shoe pressure measuring devices and the current study aimed to assess the repeatability of this device. METHODS: Twenty-seven healthy male volunteers were recruited and requested to walk on a 26-feet walkway wearing appropriate sized standardised off-the-shelf neutral running shoes (Donnay International). The Pedar-X insole was sandwiched between the foot and the shoe. Data were collected on two occasions, one week apart. Clinically relevant parameters studied were contact area, contact time in percentage roll over process, maximum force, pressure-time integral, force-time integral, peak pressure, mean force and mean area. RESULTS: Repeatability was analysed using the coefficient of variation. Of the 160 parameters considered, 93.1% revealed a coefficient of variation value of less than 25. Heel and the metatarsal head areas were the most repeatable. CONCLUSION: The Pedar-X in-shoe pressure measuring system is repeatable and as such can be used as a valuable tool in the assessment of in-shoe plantar pressure distribution.

Foot pressure differences in men and women.

BACKGROUND: Women and men are anatomically and physiologically different in a number of ways. Anthropometric studies have shown considerable differences in the foot bones of both genders. These differences could potentially mean different foot pressures in men and women. OBJECTIVE: The aim of our study was to investigate any potential foot pressure differences between males and females using the Pedar-M (Novel gmbh, Germany) in-shoe foot pressure measurement system. METHODS: Twenty-eight subjects (16 females and 12 males) were recruited. Peak pressure, contact area, contact time, pressure-time integral, force-time integral, instant of peak pressure, maximum force and mean force were recorded and subsequently analysed. RESULTS: In males, contact area was significantly larger in all regions of the foot compared with females. There were no significant between gender differences in peak pressure, contact time, pressure-time integral and instant of peak pressure. Force-time integral was significantly greater in males than females under the 1st, 3rd, and 4th metatarsal heads. Maximum force was also significantly higher in males under the heel, 1st and 3rd metatarsal heads. Mean force was greater in males under the 3rd metatarsal head. CONCLUSION: There were no peak pressure differences; however the contact area of the male foot was larger than that in females.

Foot pressure in clubfoot--the development of an objective assessment tool.

BACKGROUND: There are no universal criteria for the assessment of clubfoot. The ideal method should assess functional deformity reliably and objectively. Biomechanical techniques have also been suggested but their role remains undefined. OBJECTIVE: This study aimed to assess surgically corrected clubfeet by biomechanical means with the intention to develop certain ratios to aid in objective assessment. METHODS: Thirteen children (16 feet) with idiopathic clubfoot, who had previously undergone surgery (lateral-posteromedial release), were reviewed. Various clinical measurements were collected and symptoms assessed using a specially designed questionnaire. Biomechanical (foot pressure) parameters were obtained using two systems: Podotrack and Dynamic Pedobarograph. RESULTS: The results showed that foot pressure data were able to demonstrate abnormalities in foot posture and pressure distribution, which could objectively identify clubfoot deformities. In particular, ratios were calculated, which could be used to determine severity and monitor progression. CONCLUSION: This study suggests that foot pressure analysis should be routinely used in the assessment of clubfoot. The ratios calculated would be of immense help to the clinicians in monitoring the success of treatment and for early prediction of relapse in patients treated for clubfoot.

Adapting the Fastrak system for three-dimensional measurement of the motion of the wrist.

The Polhemus Fastrak short-range miniature transmitter and mini-receivers allow wrist motion to be measured continually in three dimensions, registering patterns of motion, which until now were difficult to quantify. The current study aimed to determine the applicability and repeatability of the Fastrak system when assessing wrist movements during a set protocol of activities. The device was found to be easy to use and repeatable; the Fastrak system showed a mean error of up to 3 degrees in all movements tested. Its assessment of range of motion correlated with the results in the literature. The Fastrakv system was suitable for continuous registration of movements during the performance of set tasks in either of the wrists. It has the potential to be used for documentation of wrist motion in clinics for various pathologies and for assessing outcomes in wrist surgeries.

The sleep apnea syndrome.

Four patients with sleep apnea syndrome were seen at the Vancouver General Hospital within the last three years and are discussed in this paper. The history of recognition of the syndrome, the types of apnea, and method of evaluation using polysomnographic techniques are reviewed, and methods of treatment are outlined.