[A prospective comparative study on effectiveness of single versus continuous adductor canal block combined with local infiltration anesthesia in unicompartmental knee arthroplasty]

Objective

To compare the early analgesic effects and the impact on knee joint function recovery after unicompartmental knee arthroplasty (UKA) between single adductor canal block (SACB) and continuous adductor canal block (CACB) combined with local infiltration anesthesia (LIA) using a prospective study.

Methods

The patients with knee osteoarthritis admitted between April 2022 and December 2023 were enrolled as a subject. Among them, 60 patients met the selection criteria and were enrolled in the study. They were randomly assigned to the SACB group or CACB group in a ratio of 1:1 using a random number table method. There was no significant difference between the two groups ( P>0.05) in terms of age, gender, height, body mass, body mass index, affected side, and preoperative resting visual analogue scale (VAS) score and active VAS score, Oxford knee score (OKS), and American Hospital of Special Surgery (HSS) score. All patients received multimodal analgesia management using LIA combined with SACB or CACB. The operation time, pain related indicators (resting and activity VAS scores, number and timing of breakthrough pain, opioid consumption), joint function related indicators (quadriceps muscle strength, knee range of motion, OKS score, and HSS score), as well as postoperative block complications and adverse events were recorded and compared between the two groups.

Results

There was no significant difference in the operation time between the two groups ( P<0.05). All patients in the two groups were followed up with a follow-up time of (9.70±4.93) months in the SACB group and (12.23±5.05) months in the CACB group, and the difference was not significant ( P>0.05). The CACB group had a significant lower resting VAS score at 24 hours after operation compared to the SACB group ( P<0.05). There was no significant difference in resting and active VAS scores between the two groups at other time points ( P>0.05). The CACB group had a significantly lower incidence of breakthrough pain compared to the SACB group [9 cases (30.00%) vs. 17 cases (56.67%); P<0.05). However, there was no significant difference in the timing of breakthrough pain occurrence and opioid consumption between the two groups ( P>0.05). Four cases in the SACB group and 7 cases in the CACB group experienced adverse events, with no significant difference in the incidence of adverse events between the two groups ( P>0.05). The CACB group had significantly better knee joint mobility than the SACB group at 1 and 2 days after operation ( P<0.05). There was no significant difference between the two groups in knee joint mobility on 0 day after operation and quadriceps muscle strength and OKS and HSS scores at different time points ( P>0.05).

Conclusion

In UKA, the analgesic effects and knee joint function recovery are similar when compared between LIA combined with SACB and LIA combined with CACB. However, SACB is simpler to perform and can avoid adverse events such as catheter displacement and dislocation. Therefore, SACB may be a better choice.

A Partial Frontal Fracture of the Humeral Trochlea: A Case Report

Fractures of the lower end of the humerus are uncommon but serious, potentially compromising elbow function. This article reports the case of a young patient with a fracture of the inner cheek of the humeral trochlea, resulting from a public road accident. The diagnosis was established by radiography and CT scan, confirming a displaced fracture associated with an avulsion fracture of the coronoid process. Surgical treatment was carried out with fixation of the osteochondral fragment and evacuation of the intra-articular fragments. Two months after the operation, the patient regained good joint function with a resumption of professional activity.

Measures of attributes of locomotor capacity in older people: a systematic literature review following the COSMIN methodology

BACKGROUND

Locomotor capacity (LC) is an important domain of intrinsic capacity and key determinant of functional ability and well-being in older age. The United Nations Decade of Healthy Ageing (2021-2030) calls for strengthening data and research on healthy ageing, including the measurement of older persons' LC. To advance the measurement and monitoring of LC, there is pressing need to identify valid and reliable measures.

OBJECTIVE

To identify all the available tools that were validated for measurement of LC or of its specific attributes in older people and to assess the methodological quality of the studies and measurement properties of the tools.

DESIGN

Systematic review.

SETTING

Anywhere (Community-dwelling; long-term care facility; etc.).

SUBJECTS

Older people.

METHODS

We used highly sensitive search strategies to search the following databases: Medline, Embase, Scopus, CINAHL and PsycINFO. The study was conducted following the COnsensus-based Standards for the selection of health Measurement Instruments (COSMIN) methodology for systematic review of outcome measurement instruments.

RESULTS

A total of 125 studies were included, which assessed tools for balance (n = 84), muscle power (n = 12), muscle strength (n = 32, including four studies about tools for balance and muscle power) and endurance (n = 1). No studies on tools for muscle function, joint function, or locomotor capacity overall, were retrieved. We identified 69 clinician-report or objective assessment tools for balance, 30 for muscle strength, 12 for muscle power and 1 endurance assessment tool. The GRADE assessment of quality of evidence showed that only a few tools have high quality evidence for both sufficient validity and reliability: The Balance Evaluation Systems Test (BESTest), the Mini-Balance Evaluation Systems Test (Mini-BESTest), the Berg Balance Scale (BBS) and the Timed Up and Go (TUG) test.

CONCLUSIONS

A few tools with high quality evidence for sufficient validity and reliability are currently available for balance assessment in older people that may be recommended for use in clinical and research settings. Further validation studies are required for muscle strength, muscle power and endurance assessment tools.

Magnitude and direction of elbow torque asymmetries in manual wheelchair users

The aims of the present study are to investigate the magnitude and direction of the elbow torque asymmetries in manual wheelchair users and to verify the agreement levels of the asymmetry's direction between different velocities and contraction modes in the isokinetic test. The sample was composed of 14 manual wheelchair users (four women, 10 men). The peak torque of the elbow flexors and extensors were measured on the dominant and non-dominant limbs, using a set of concentric/eccentric contractions at speeds of 60° s-1 and 180° s-1. Asymmetries were calculated by a specific equation, and the levels of agreement of the asymmetry's direction were calculated using Kappa coefficient. The main results showed a large variability in the magnitude of the asymmetries, ranging from -73.1% (ND) to 59.9% (D) between participants. The agreement levels of the elbow flexors and extensors between the different contraction modes were great (k = 0.71-0.85) for most of the velocities [except for flexors of 60° s-1 (k = 0.29)], but the agreement levels were only slight to fair (k = 0.16-0.31) for most of the contraction modes when comparing between velocities [except for flexors eccentric (k = 0.71)]. In conclusion, the elbow torque asymmetries are highly variable between subjects in terms of magnitude. In addition, in general, the limb favored by the asymmetry is the same when comparing between velocities, but not when comparing between contraction modes.

Effects of joint irrigation combined with ozone injection on bone metabolism, inflammatory factors, and joint function in knee osteoarthritis

OBJECTIVE

To explore the effects of joint irrigation combined with ozone injection on bone metabolism, inflammatory factors, and joint function in patients with knee osteoarthritis (KOA).

METHOD

In this retrospective study, a total of 132 KOA patients admitted to No. 215 Hospital of Shaanxi Nuclear Industry from October 2019 to July 2021 were enrolled. Among them, 62 patients received arthroscopic irrigation alone were assigned into a control group, and the remaining 70 patients who received arthroscopic irrigation combined with ozone injection were assigned into an observation group. Therapeutic efficacy and adverse reactions during the treatment were compared in the two groups. Bone metabolism, inflammatory factor levels and joint function of patients before and after treatment were observed; patients were further divided into a good prognosis group and a poor prognosis group regarding their prognosis. Multivariate analysis was performed to explore the independent risk factors affecting prognosis.

RESULTS

After treatment, compared to the control group, the total effective rate of the observation group was higher (P<0.05), and there was no notable difference in the incidence of adverse reactions between the two groups (P>0.05). The bone metabolism indexes, osteocalcin (OC) and osteoprotegerin (OPG), in the observation group were also significantly higher (P<0.05), while the level of nuclear transcription factor κB receptor activator ligand (RANKL) in the observation group was markedly lower. The inflammation level in the observation group was lower (P<0.05). Lysholm score in the observation group was strikingly higher (P<0.05), while its Western Ontario McMaster (WOMAC) score and visual analogue scale (VAS) were lower (P<0.05). The observation group had a lower rate of poor prognosis (P<0.05). Age (OR: 1.786, 95% CI: 1.347-2.370), disease duration (OR: 1.132, 95% CI: 1.002-1.279), VAS after treatment (OR: 2.316, 95% CI: 1.089-4.925), and post-treatment IL-6 (OR: 1.186, 95% CI: 1.017-1.382) were all independent risk factors for poor prognosis.

CONCLUSION

Joint irrigation combined with ozone injection shows good efficacy in the treatment of KOA, and could effectively relieve the clinical symptoms of patients, improve their bone metabolism indexes, and help the recovery of knee joint function.

Shared Decision-Making in Hemophilic Arthropathy Rehabilitation: A Qualitative Study

PURPOSE

To probe into the needs and barriers underlying patients' participation in shared decision-making related to rehabilitation nursing for hemophilic arthropathy.

PATIENTS AND METHODS

The phenomenological research approach was adopted to conduct a series of semi-structured, in-depth interviews with 15 patients with hemophilic arthropathy undergoing rehabilitative treatments, 10 caregivers, and 7 healthcare providers from a hemophilia treatment center in Shanxi province, China. Colaizzi's seven-step method of data analysis was applied to organize, analyze, and extract the themes from the interview materials.

RESULTS

Three main themes emerged from the analysis: the status quo of the healthcare system (insufficient decision support systems and mismatch between healthcare providers' and patients' resources), circumstances of provider-patient interactions (lack of information exchange and unbalanced power structure between healthcare providers and patients), and patient-related factors influencing participation in decision-making (lack of self-efficacy, personal characteristics, family and social decision support, and attitude toward participation in decision-making).

CONCLUSION

Participation in rehabilitation decision-making among patients with hemophilic arthropathy is affected by multiple barriers. Healthcare professionals should improve their understanding of shared decision-making, offer patients active guidance on participating in the decision-making process, prioritize their affective needs, and formulate professional and effective solutions to support shared decision-making as early as possible.

Achilles Tendon Mechanical Behavior and Ankle Joint Function at the Walk-to-Run Transition

Walking at speeds higher than transition speed is associated with a decrease in the plantar-flexor muscle fibres’ ability to produce force and, potentially, to an impaired behaviour of the muscle−tendon unit (MTU) elastic components. This study aimed to investigate the ankle joint functional indexes and the Achilles tendon mechanical behaviour (changes in AT force and power) to better elucidate the mechanical determinants of the walk-to-run transition. Kinematics, kinetic and ultrasound data of the gastrocnemius medialis (GM) were investigated during overground walking and running at speeds ranging from 5−9 km·h−1. AT and GM MTU force and power were calculated during the propulsive phase; the ankle joint function indexes (damper, strut, spring and motor) were obtained using a combination of kinetic and kinematic data. AT force was larger in running at speeds > 6.5 km/h. The contribution of AT to the total power provided by the GM MTU was significantly larger in running at speeds > 7.5 km/h. The spring and strut indexes of the ankle were significantly larger in running at speeds > 7.5 km/h. These data suggest that the walk-to-run transition could (at least partially) be explained by the need to preserve AT mechanical behaviour and the ankle spring function.

Collagen I in the Hip Capsule Plays a Role in Postoperative Clinical Function in Patients With Developmental Dysplasia of the Hip

The aims of the present study is to evaluate the roles of collagen I and III in the hip capsule in the postoperative clinical function of patients with developmental dysplasia of the hip (DDH). Hip capsules from 155 hips of 120 patients were collected during surgery. The patients were divided into three groups according to age: I: 2-3.5 years; II: 3.5-5 years; and III: 5-6 years. Patient clinical function and radiographic outcomes were evaluated with the McKay scores and Severin classification. The expression of collagen I and III was detected through immunohistochemistry and quantitative reverse transcription polymerase chain reaction (RT-PCR) and analyzed according to age, sex, degree of dislocation and McKay classification. All patients received open reduction and pelvic osteotomy and/or femoral shortening osteotomy and achieved good results on the basis of postoperative X-ray imaging. The average follow-up time was 3.4 years (range 2-4.3 years). There were no changes in the expression of collagen III in the different groups. The expression of collagen I according to age and sex was not significantly different. Lower expression of collagen I was observed in DDH patients with a higher degree of dislocation according to the Tonnis grade. The highest expression of collagen I was detected in the group with poor clinical function according to the McKay classification. Collagen I is correlated with the degree of dislocation and is a risk factor for poor clinical function in DDH patients. Collagen I is correlated with the degree of hip dislocation and poor clinical function in DDH patients.

Effects of intramedullary nailing fixation on quality of life and joint function in patients with femoral neck fractures

OBJECTIVE

This study intended to investigate the changes in quality of life and joint function after intramedullary nailing fixation in patients with femoral neck fractures.

METHODS

A total of 38 patients with femoral neck fractures received surgical treatment from February 2016 to November 2018 were enrolled as study subjects, and were divided into the intramedullary nailing group (IIN group, n=13) and the plate fixation group (PO group, n=25). The efficacy, general surgical indices, postoperative complications, hip function scores and imaging results were compared between the two groups.

RESULTS

The response rate of the IIN group was 100.00%, significantly higher than 72.00% of the PO group (P<0.05). The length of hospital stay, blood loss, and the length of the healing period in the IIN group were lower than those in the PO group (P<0.05). The incidence of infection, deformity, loosening of internal fixation, and failed internal fixation in the PO group were significantly higher those than in the INN group (P<0.05). At 3, 6, and 12 months after surgery, the INN group had higher Harris scores and SF-36 scores than the PO group (P<0.05). The response rates of Harris scores of patients in the IIN group were significantly higher than those in the PO group at 12 months postoperatively (P<0.05).

CONCLUSION

Intramedullary nailing fixation in patients with femoral neck fractures has the advantages of a shorter time in bed and better functional recovery, lower incidence of complications and higher long-term joint function with better quality of life.

The Effect of Local Heat Therapy versus Cold Rub Gel on Pain and Joint Functions in Patients with Knee Osteoarthritis

This study was compared the effect of local heat therapy versus cold rub gel on pain and joint function in patients with knee osteoarthritis. One hundred seventeen patients with knee osteoarthritis were randomly assigned to cold rub gel, local heat therapy, and control group. Data were collected by knee injury and osteoarthritis outcome score at a week prior to the interventions and on weeks of 1, 2, 3, and 4 of the interventions. A significant difference was found between the three groups in terms of pain severity (p = .001), joint symptoms (p = .001), ADL function (p = .001), Sport and Recreation function (p = .001), except Knee related QOL (p = .3). Cold rub gel and heat therapy were both effective in improving pain and joint function in patients with knee osteoarthritis.

Speed-Related Energy Flow and Joint Function Change During Human Walking

During human walking, mechanical energy transfers between segments via joints. Joint mechanics of the human body are coordinated with each other to adapt to speed change. The aim of this study is to analyze the functional behaviors of major joints during walking, and how joints and segments alter walking speed during different periods (collision, rebound, preload, and push-off) of stance phase. In this study, gait experiment was performed with three different self-selected speeds. Mechanical works of joints and segments were determined with collected data. Joint function indices were calculated based on net joint work. The results show that the primary functional behaviors of joints would not change with altering walking speed, but the function indices might be changed slightly (e.g., strut functions decrease with increasing walking speed). Waist acts as strut during stance phase and contributes to keep stability during collision when walking faster. Knee of stance leg does not contribute to altering walking speed. Hip and ankle absorb more mechanical energy to buffer the strike during collision with increasing walking speed. What is more, hip and ankle generate more energy during push-off with greater motion to push distal segments forward with increasing walking speed. Ankle also produces more mechanical energy during push-off to compensate the increased heel-strike collision of contralateral leg during faster walking. Thus, human may utilize the cooperation of hip and ankle during collision and push-off to alter walking speed. These findings indicate that speed change in walking leads to fundamental changes to joint mechanics.

The efficiency of internal fixation with bone grafting at docking sites after bone transport for treatment of large segmental tibial bone defects

OBJECTIVE

To investigate the efficiency of internal fixation with bone grafting after bone transport for treatment in large-segment bone defects of the lower-limbs.

METHODS

This prospective study recruited 100 patients with lower limb tibial segmental bone defects, and based on a random number table they were divided into a control group (n=50, simple bone transport surgery) or an observation group (n=50, internal fixation with bone grafting at docking site after bone transport). The fracture healing time, bone healing index, external fixation time in both groups were compared. The knee function, joint range of motion, and the function of the ankle and hindfoot before and after surgery were also analyzed and compared between the two groups respectively, as well as the rate of complications in both groups was calculated.

RESULTS

Compared with the preoperative condition of patients, the Lysholm knee scale, ROM score, and AHS scores of patients in the two groups were significantly increased 10 months after surgery, moreover, those scores of the observation group were higher than that of the control group (P<0.05). The fracture healing time and external fixation time of patients were significantly declined in the observation group when compared to the control group, additionally, the bone healing index was also reduced significantly (P<0.05). When compared with patients in the control group, the ratios of bone healing and lower-limb functional recovery of patients in the observation group were significantly higher while the total complication incidence was decreased remarkably (P<0.05).

CONCLUSION

Internal fixation with bone grafting after bone transport can promote fracture healing, improve joint function, and reduce complications during treatment for a large segmental bone defects in the lower limbs.

Do Surface Slope and Posture Influence Lower Extremity Joint Kinetics during Cycling?

The purpose of this study was to investigate the effects of surface slope and body posture (i.e., seated and standing) on lower extremity joint kinetics during cycling. Fourteen participants cycled at 250 watts power in three cycling conditions: level seated, uphill seated and uphill standing at a 14% slope. A motion analysis system and custom instrumented pedal were used to collect the data of fifteen consecutive cycles of kinematics and pedal reaction force. One crank cycle was equally divided into four phases (90° for each phase). A two-factor repeated measures MANOVA was used to examine the effects of the slope and posture on the selected variables. Results showed that both slope and posture influenced joint moments and mechanical work in the hip, knee and ankle joints (p < 0.05). Specifically, the relative contribution of the knee joint to the total mechanical work increased when the body posture changed from a seated position to a standing position. In conclusion, both surface slope and body posture significantly influenced the lower extremity joint kinetics during cycling. Besides the hip joint, the knee joint also played the role as the power source during uphill standing cycling in the early downstroke phase. Therefore, adopting a standing posture for more power output during uphill cycling is recommended, but not for long periods, in view of the risk of knee injury.

Effect of a Moderate-Intensity Aerobic Training on Joint Biomarkers and Functional Adaptations in Rats Subjected to Induced Knee Osteoarthritis

Background

Knee osteoarthritis (_kOA) is a common chronic disease that induces changes in redox status and inflammatory biomarkers, cell death, and motor impairment. Aerobic training can be a non-pharmacological alternative to prevent the progression of the disease.

Objective

To evaluate the effects of an 8 weeks moderate-intensity treadmill aerobic training program on redox status and inflammatory biomarkers and motor performance in _kOA-like changes induced by monosodium iodoacetate (MIA) in rats.

Methods

Twenty-seven rats were randomly divided into three groups: SHAM; induced _kOA (OA); and induced _kOA + aerobic training (OAE). Motor performance was evaluated by the number of falls on rotarod test, the total time of displacement and the number of failures on a 100 cm footbridge. Data for cytokines and histology were investigated locally, whereas plasma was used for redox status biomarkers.

Results

The OA group, compared to the SHAM group, increased 1.13 times the total time of displacement, 6.05 times the number of failures, 2.40 times the number of falls. There was also an increase in cytokine and in thiobarbituric acid reactive substances (TBARS) (IL1β: 5.55-fold, TNF: 2.84-fold, IL10: 1.27-fold, IL6: 1.50-fold, TBARS: 1.14-fold), and a reduction of 6.83% in the total antioxidant capacity (FRAP), and of 35% in the number of chondrocytes. The aerobic training improved the motor performance in all joint function tests matching to SHAM scores. Also, it reduced inflammatory biomarkers and TBARS level at values close to those of the SHAM group, with no change in FRAP level. The number of falls was explained by IL1β and TNF (58%), and the number of failures and the total time of displacement were also explained by TNF (29 and 21%, respectively).

Conclusion

All findings indicate the efficacy of moderate-intensity aerobic training to regulate inflammatory biomarkers associated with improved motor performance in induced _kOA-like changes, thus preventing the loss of chondrocytes.

Knee joint function, walking ability and quality of life within 6 weeks after total knee arthroplasty: A prospective cohort study

AIMS AND OBJECTIVES

To track changes in patients' knee function, walking ability and quality of life (QOL) before and after knee arthroplasty surgery and explore factors that influenced these parameters.

BACKGROUND

The number of days as an inpatient for those who undergo joint replacement operations has been greatly reduced in recent years. However, it remains unclear whether shortening the inpatient time has affected patients' recovery or their QOL.

DESIGN

Prospective cohort study.

METHOD

In total, 101 participants who underwent total knee arthroplasty (TKA) were enrolled, with data collected preoperatively and at the 2nd and 6th weeks postoperatively. We followed the STROBE checklist to ensure the rigour of our study.

RESULTS

Forty-nine participants underwent unilateral TKA (UTKA; 48.5%), and 52 underwent simultaneous bilateral TKA (SBTKA; 51.5%). At the 2nd week postoperatively, knee joint function was significantly worse than that preoperatively. However, these patients did not exhibit significant differences in the EQ-5D utility index (EQ-5D UI) compared to their preoperative scores. At the 6th week postoperatively, the knee joint function and EQ-5D UI were significantly better than preoperative values. Participants who underwent UTKA scored higher on the Oxford knee score (OKS) than did SBTKA participants. However, no significant differences were noted between the two groups for the knee flexion angle, the timed up and go (TUG) test, or the EQ-5D UI score.

CONCLUSIONS AND SUGGESTIONS

At the postoperative 6th week, participants exhibited improved knee joint function and QOL, but there was no difference in the walking ability compared to preoperative values. At the 6th week after surgery, patients who underwent SBTKA exhibited poorer joint function than did those who underwent UTKA.

RELEVANCE TO CLINICAL PRACTICE

These results can assist nursing staffs and serve as a reference for providing patient education and nursing intervention to TKA patients.

[Clinical observation of expanded curettage in treatment of chondroblastoma]

Objective

To explore the effectiveness of expanded curettage in the treatment of chondroblastoma.

Methods

The clinical data of 37 patients with chondroblastoma who were treated with expanded curettage between January 2011 and May 2016 were retrospectively analyzed. There were 24 males and 13 females, with a median age of 17 years (range, 12-30 years). There were 32 primary patients and 5 recurrent patients. Local pain was the first symptom in all patients. The average disease duration was 4.9 months (range, 2-8 months). The lesions were located in the distal femur in 10 cases, the proximal femur in 7 cases, the proximal tibia in 9 cases, the proximal humerus in 5 cases, the patella in 2 cases, the talus in 1 case, the calcaneus in 1 case, and pelvis in 2 cases. According to the Enneking staging of benign bone tumors, all tumors were rated as the 3rd stage. The length of the lesion ranged from 1.2 to 6.9 cm (mean, 3.2 cm). The lesions involved the epiphyseal plate in 19 cases.

Results

All incisions healed by first intention, and no complications occurred. All patients were followed up 12-76 months, with an average of 40.5 months. At last follow-up, the Musculoskeletal Tumor Society (MSTS) score was 27.5±1.4, and the difference was significant when compared with pre-operative value (18.5±1.9) ( t=23.462, P=0.000). The chondroblastoma recurred in 1 case (2.7%) after 5 months. X-ray film showed that bone resorption was found in 6 cases, but there was no obvious collapse in the articular surface of bone graft. The limb shortening deformity occurred in 3 cases who were epiphyseal plate involvement patients and lesions located around the knee joint. But there was no varus deformity, and knee joint activity was not affected.

Conclusion

Expanded curettage has advantages of low incidence of recurrence and skeletal deformity, good limb function, and it is one of the ideal options for chondroblastoma.

Haemophilia Joint Health Score in healthy adults playing sports

To evaluate outcome of prophylactic clotting factor replacement in children with haemophilia, the Haemophilia Joint Health Score (HJHS) was developed aiming at scoring early joint changes in children aged 4-18. The HJHS has been used for adults on long-term prophylaxis but interpretation of small changes remains difficult. Some changes in these patients may be due to sports-related injuries. Evaluation of HJHS score in healthy adults playing sports could improve the interpretation of this score in haemophilic patients. The aim of this study was to evaluate the HJHS scores in a cohort of young, healthy men participating in sports. Concomitant with a project collecting MRI images of ankles and knees in normal young adults, HJHS scores were assessed in 30 healthy men aged 18-26, participating in sports one to three times per week. One physiotherapist assessed their clinical function using the HJHS 2.1. History of joint injuries was documented. MRI images were scored by a single radiologist, using the International Prophylaxis Study Group additive MRI score. Median age of the study group was 24.3 years (range 19.0-26.4) and median frequency of sports activities was three times per week (range 1-4). Six joints (five knees, one ankle) had a history of sports-related injury. The median overall HJHS score was 0 out of 124 (range 0-3), with 60% of subjects showing no abnormalities on HJHS. All joints were normal on MRI. These results suggest that frequent sports participation and related injuries are not related with abnormalities in HJHS scores.

Undenatured type II collagen (UC-II®) for joint support: a randomized, double-blind, placebo-controlled study in healthy volunteers

BACKGROUND

UC-II contains a patented form of undenatured type II collagen derived from chicken sternum. Previous preclinical and clinical studies support the safety and efficacy of UC-II in modulating joint discomfort in osteoarthritis and rheumatoid arthritis. The purpose of this study was to assess the efficacy and tolerability of UC-II in moderating joint function and joint pain due to strenuous exercise in healthy subjects.

METHODS

This randomized, double-blind, placebo-controlled study was conducted in healthy subjects who had no prior history of arthritic disease or joint pain at rest but experienced joint discomfort with physical activity. Fifty-five subjects who reported knee pain after participating in a standardized stepmill performance test were randomized to receive placebo (n = 28) or the UC-II (40 mg daily, n = 27) product for 120 days. Joint function was assessed by changes in degree of knee flexion and knee extension as well as measuring the time to experiencing and recovering from joint pain following strenuous stepmill exertion.

RESULTS

After 120 days of supplementation, subjects in the UC-II group exhibited a statistically significant improvement in average knee extension compared to placebo (81.0 ± 1.3º vs 74.0 ± 2.2º; p = 0.011) and to baseline (81.0 ± 1.3º vs 73.2 ± 1.9º; p = 0.002). The UC-II cohort also demonstrated a statistically significant change in average knee extension at day 90 (78.8 ± 1.9º vs 73.2 ± 1.9º; p = 0.045) versus baseline. No significant change in knee extension was observed in the placebo group at any time. It was also noted that the UC-II group exercised longer before experiencing any initial joint discomfort at day 120 (2.8 ± 0.5 min, p = 0.019), compared to baseline (1.4 ± 0.2 min). By contrast, no significant changes were seen in the placebo group. No product related adverse events were observed during the study. At study conclusion, five individuals in the UC-II cohort reported no pain during or after the stepmill protocol (p = 0.031, within visit) as compared to one subject in the placebo group.

CONCLUSIONS

Daily supplementation with 40 mg of UC-II was well tolerated and led to improved knee joint extension in healthy subjects. UC-II also demonstrated the potential to lengthen the period of pain free strenuous exertion and alleviate the joint pain that occasionally arises from such activities.