Total knee arthroplasty reduces knee extension torque in-vitro and patellofemoral arthroplasty does not (2020)

Type of publication:
Journal article

Author(s):
Joseph M.N.; Stephen J.M.; Amis A.A.; *Carmont M.R.; Tailor H.

Citation:
Journal of Biomechanics; May 2020, Volume 104 [epub ahead of print]

Abstract:
Patients often have difficulty recovering knee extension strength post total knee arthroplasty (TKA), and that may reflect alteration of the mechanics including geometry and rollback kinematics, so the purpose of this work was to explore this by comparing the knee extension torque (KET) of the native knee, TKA and patellofemoral arthroplasty (PFA) in response to quadriceps tension. Eight fresh-frozen knees were mounted in a knee extension rig with quadriceps loading and tibial extension torque measurement. Each knee was subject to four conditions: native knee, PFA, cruciate-retaining (CR) and posterior-stabilized (PS) TKA. The KET was measured from 120degree to 0degree knee flexion. Data were analyzed using one-way ANOVA and post-hoc paired t-tests. The native KET was lowest in terminal extension and 70-100degree flexion, and maximal at 20-30degree flexion. PFA produced the greatest KET (p < 0.008) compared with native, CR- and PS-TKA, at 30-40degree flexion. CR- and PS-TKA had lower KET across 0-50degree flexion (p < 0.001 across 0-30degree), falling to 25% of the native knee KET or the PFA at full extension. PFA had the highest KET in early flexion possibly due to increased trochlear offset and/or preservation of the cruciate mechanism, so PFA may be more beneficial during the functional range of motion. The claimed benefits of PS- over CR-TKA in deep flexion were not detected. Both CR- and PS-TKAs led to lower KET than the native and PFA knee states across 0-50degree flexion. This mechanical effect may help to explain clinical findings of knee extension weakness post-TKA.

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An Epidemiological Study of Foot and Ankle Motocross Motorcycling Injuries in the United Kingdom (2020)

Type of publication:
Journal article

Author(s):
*Orfanos G.; *Paavana T.; *Hill S.O.; *Singh R.A.; *Hay S.M.

Citation:
Foot and Ankle Surgery; Oct 2020; vol. 26 (no. 7); p. 797-800

Abstract:
Background: Motocross is a recreational and competitive sport involving motorcycle racing on off-road circuits. Participants have enjoyed their sport worldwide for over 100 years. In the United Kingdom, there are over 200 clubs, with over 900 events annually. Unfortunately, little evidence exists on motocross injuries and their prevention. The aim of this study is to report and to quantify the different foot and ankle injuries observed in motocross.
Method(s): Data was collected prospectively between August 2010 to August 2015 at our regional trauma unit, regardless of whether the sport was performed competitively or recreationally.
Result(s): Foot and ankle related injuries were identified in 210 patients (age range 4-78 years), with the majority being male participants (189, 90%). The majority of injuries occurred within the 21- to 30-year-old-age group. Most injuries were sustained around the start of the motocross season, in early spring and the summer months. A total of 76 patients (36%) required operative intervention. The most common injury was ankle fracture (49, 23%), followed by ankle sprain (44, 21%).
Conclusion(s): This is the first epidemiological study in the United Kingdom documenting foot and ankle injuries in motocross. The frequency and severity of motocross-related injuries is presented. This may serve to provide recommendations and guidelines in the governing bodies of this sport. The surge in motocross popularity is correlates with an increase in injuries and inevitably the resources required to treat them.
Level of Evidence: Prospective descriptive epidemiological study. Level 1.

Tendon end separation with loading in an Achilles tendon repair model: comparison of non-absorbable vs. absorbable sutures (2017)

Type of publication:
Journal article

Author(s):
*Carmont, Michael R; Kuiper, Jan Herman; Grävare Silbernagel, Karin; Karlsson, Jón; Nilsson-Helander, Katarina

Citation:
of experimental orthopaedics; Dec 2017; vol. 4 (no. 1); p. 26

Abstract:
BACKGROUND Rupture of the Achilles tendon often leads to long-term morbidity, particularly calf weakness associated with tendon elongation. Operative repair of Achilles tendon ruptures leads to reduced tendon elongation. Tendon lengthening is a key problem in the restoration of function following Achilles tendon rupture. A study was performed to determine differences in initial separation, strength and failure characteristics of differing sutures and numbers of core strands in a percutaneous Achilles tendon repair model in response to initial loading.METHODSNineteen bovine Achilles tendons were repaired using a percutaneous/ minimally invasive technique with a combination of a modified Bunnell suture proximally and a Kessler suture distally, using non-absorbable 4-strand 6-strand repairs and absorbable 8-strand sutures. Specimens were then cyclically loaded using phases of 10 cycles of 100 N, 100 cycles of 100 N, 100 cycles of 190 N consistent with  early range of motion training and weight-bearing, before being loaded to failure.RESULTS Pre-conditioning of 10 cycles of 100 N resulted in separations of 4 mm for 6-strand, 5.9 mm for 4-strand, but 11.5 mm in 8-strand repairs, this comprised 48.5, 68.6 and 72.7% of the separation that occurred after 100 cycles of 100 N. The tendon separation after the third phase of 100 cycles of 190 N was 17.4 mm for 4-strand repairs, 16.6 mm for 6-strand repairs and 26.6 mm for 8-strand repairs. There were significant differences between the groups (p < 0.0001). Four and six strand non-absorbable repairs had significantly less separation than 8-strand absorbable repairs (p = 0.017 and p = 0.04 respectively). The mean (SEM) ultimate tensile strengths were 4-strand 464.8 N (27.4), 6-strand 543.5 N (49.6) and 8-strand 422.1 N (80.5). Regression analysis reveals no significant difference between the overall strength of the 3 repair models (p = 0.32) (4 vs. 6: p = 0.30, 4 vs. 8: p = 0.87; 6 vs. 8: p = 0.39). The most common mode of failure was pull out of the Kessler suture from the distal stump in 41.7% of specimens. CONCLUSION The use of a non-absorbable suture resulted in less end-to-end separation when compared to absorbable sutures when an Achilles tendon repair model was subject to cyclical loading. Ultimate failure occurred more commonly at the distal Kessler suture end although this occurred with separations in excess of clinical failure. The effect of early movement and loading on the Achilles tendon is not fully understood and requires more research.

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Tendon end separation with loading in an Achilles tendon repair model: comparison of non-absorbable vs. absorbable sutures (2017)

Type of publication:
Journal article

Author(s):
*Carmont M.R.; Kuiper J.H.; Gravare Silbernagel K.; Karlsson J.; Nilsson-Helander K.

Citation:
Journal of Experimental Orthopaedics; Dec 2017; vol. 4 (no. 1)

Abstract:
Background: Rupture of the Achilles tendon often leads to long-term morbidity, particularly calf weakness associated with tendon elongation. Operative repair of Achilles tendon ruptures leads to reduced tendon elongation. Tendon lengthening is a key problem in the restoration of function following Achilles tendon rupture. A study was performed to determine differences in initial separation, strength and failure characteristics of differing sutures and numbers of core strands in a percutaneous Achilles tendon repair model in response to initial loading. Methods: Nineteen bovine Achilles tendons were repaired using a percutaneous/minimally invasive technique with a combination of a modified Bunnell suture proximally and a Kessler suture distally, using non-absorbable 4-strand 6-strand repairs and absorbable 8-strand sutures. Specimens were then cyclically loaded using phases of 10 cycles of 100 N, 100 cycles of 100 N, 100 cycles of 190 N consistent with early range of motion training and weight-bearing, before being loaded to failure. Results: Pre-conditioning of 10 cycles of 100 N resulted in separations of 4 mm for 6-strand, 5.9 mm for 4-strand, but 11.5 mm in 8-strand repairs, this comprised 48.5, 68.6 and 72.7% of the separation that occurred after 100 cycles of 100 N. The tendon separation after the third phase of 100 cycles of 190 N was 17.4 mm for 4-strand repairs, 16.6 mm for 6-strand repairs and 26.6 mm for 8-strand repairs. There were significant differences between the groups (p < 0.0001). Four and six strand non-absorbable repairs had significantly less separation than 8-strand absorbable repairs (p = 0.017 and p = 0.04 respectively). The mean (SEM) ultimate tensile strengths were 4-strand 464.8 N (27.4), 6-strand 543.5 N (49.6) and 8-strand 422.1 N (80.5). Regression analysis reveals no significant difference between the overall strength of the 3 repair models (p = 0.32) (4 vs. 6: p = 0.30, 4 vs. 8: p = 0.87; 6 vs. 8: p = 0.39). The most common mode of failure was pull out of the Kessler suture from the distal stump in 41.7% of specimens. Conclusion: The use of a non-absorbable suture resulted in less end-to-end separation when compared to absorbable sutures when an Achilles tendon repair model was subject to cyclical loading. Ultimate failure occurred more commonly at the distal Kessler suture end although this occurred with separations in excess of clinical failure. The effect of early movement and loading on the Achilles tendon is not fully understood and requires more research.

Mortality and burden of cervical spine fractures in the elderly: can we do more? (2017)

Type of publication:
Conference abstract

Author(s):
*Matthew Chan, *Benjamin Chatterton, *David Ford

Citation:
Spine Journal; Mar 2017; vol. 17 (no. 3), S20

Abstract:
BACKGROUND CONTEXT: Cervical spine fractures in the elderly are a significant injury that poses difficult treatment dilemmas. Despite this little has been done to evaluate the mortality and hospital burden. PURPOSE: Evaluate the mortality and hospital burden associated with cervical spine fractures in elderly patients at district general hospitals. STUDY DESIGN/SETTING: 10-year retrospective analysis of patients over the age of 70 presenting with a cervical spine fracture to two district general hospitals. METHODS: The data was collected from documentation on online hospital database systems. Data recorded included patient demographics, injuries sustained including level and mechanism of cervical injury, length of stay and details on inpatient complications, inpatient mortality and one-year mortality. RESULTS: 153 patients were identified with a mean age of 83, and slight female predominance (55%). Mechanical falls (90%) leading to isolated fractures of upper cervical spine, particularly C2 (52%), were the most common site and mechanism of injury. Inpatient mortality was 22.9%, and 1-year mortality was calculated at 35.3%. Inpatient medical complications, particularly chest infections, were common and occurred in 35.9% of patients. Total average length of stay was 18 days, and critical care input was required in 10.5% of patients. CONCLUSIONS: Cervical spine fractures in the elderly cause significant mortality and hospital burden. Medical complications are common, leading to increased morbidity and length of stay. Consideration should be made to develop national guidance akin to hip fractures. This would encourage a multidisciplinary team approach, including early input from medical and physiotherapy teams to ensure more effective treatment and prevention of complications.

Ultrasound guided musculoskeletal interventions: professional opportunities, challenges and the future of injection therapy (2015)

Type of publication:
Journal article

Author(s):
Sue Innes, Mark Maybury, Alison Hall, *Gordon Lumsden

Citation:
Sonography (2015) 2(4): 84-91

Abstract:
The demand for ultrasound guided injections for musculoskeletal presentations has increased in recent years as practitioners and patients seek verification of needle position. Musculoskeletal management pathways regularly include injection therapy for pain relief and are sometimes indicated as a single intervention but may need to be supported by rehabilitation. Workload in radiology departments has expanded in volume and complexity as radiologists perform new interventional procedures that require medical expertise. Innovative responses are required to meet the demand for ultrasound guided musculoskeletal injections; one option is offering appropriate education to musculoskeletal sonographers, enabling them to extend their current scope of practice. The role of the extended scope physiotherapist in the United Kingdom provides evidence that role diversification can produce excellent patient outcomes whilst preserving financial resources. The professional, legal and clinical requirements of extending service provision to include new clinical staff presents challenges that have to be met with strong leadership and the provision of high quality education in ultrasound guided interventions. There are many indicators that the patient experience is enhanced by guiding musculoskeletal injections, and access to this service has impact on patients’ confidence in their treatment pathway.

Growth plate injuries and management (2015)

Type of publication:
Journal article

Author(s):
*Dover C., Kiely N.

Citation:
Orthopaedics and Trauma, August 20 15, vol./is. 29/4(261-267)

Abstract:
The growth plate, or physis, is the name given to the area of cartilaginous tis sue found between the epiphysis and metaphysis of skeletally immature bone. The developing growth plate is weaker than surrounding ossified bone and, therefore, at risk of injury before its closure. Previous studies have shown that fractures account for 10-25% of all paediatric injuries, with growth plate injuries accounting for 15-30% of all paediatric bony injury. The upper limb is most likely to be affected, with the distal radius found to be the most common site of fractures in children. The Salter-Harris classification describes growth plate injuries based upon location and likelihood of growth arrest. In addition to growth arrest, injury to the growth plate often stimulates bone repair, which can lead to limb length discrepancy, bone b ridge formation between the metaphysis and epiphysis, and angulation of the bone. The treatment of growth plate fractures ranges from conservative management to operative fixation and bone grafting. Outcome is varied and dependent upon site and grade of the fracture as well as the age of the patient. Regardless of Salter-Harris classification, an important component of management is counselling the parents about the potential risk of future growth arrest and associated sequelae.

Calcaneus osteotomy (2014)

Type of publication:
Journal article

Author(s):
Tennant J.N., *Carmont M., Phisitkul P.

Citation:
Current Reviews in Musculoskeletal Medicine, 2014, vol./is. 7/4(271-276), 1935-973X;1935-9748 (2014)

Abstract:
Calcaneal osteotomy is an extra-articular, joint-sparing procedure that is used in the correction of cavovarus and planovalgus foot deformity. Careful indications and contraindications for the procedure, with meticulous surgical technique, should be followed to avoid complications and to achieve optimal outcomes. Multiple options of osteotomies exist, including translational (medializing and lateralizing calcaneal osteotomy, with ability to slide proximally or distally, closing wedge (Dwyer), and rotational type osteotomies (Evans, Z-osteotomy). Future directions for innovation include developments of both implants and surgical techniques.

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Anatomy of the sural nerve and its relation to the achilles tendon by ultrasound examination (2014)

Type of publication:
Journal article

Author(s):
Kammar H., *Carmont M.R., Kots E., Laver L., Mann G., Nyska M., Mei-Dan O.

Citation:
Orthopedics, March 2014, vol./is. 37/3(e298-e301), 0147-7447 (March 2014)

Abstract:
Sural nerve injury is a relatively common complication after surgery on the Achilles tendon. Studies to determine the course of the sural nerve have been performed on cadaveric specimens. The purpose of this cross-sectional study was to use ultrasound to determine the relations of the sural nerve in a healthy population. The authors performed ultrasound examination of the posterior triangle of the ankle and Achilles tendon to determine the course of the sural nerve relative to the Achilles tendon in healthy participants. The mean distance between the nerve and the tendon was 21.48, 11.47, 5.8, and 0.81 mm lateral to the Achilles tendon as measured at the insertion and 4, 8, and 11 cm proximally, respectively. Male participants tended to have a nerve that was initially more lateral to the Achilles insertion compared with women. The distance between the sural nerve and the Achilles tendon was found to be lower in older participants, with the nerve passing significantly closer to the tendon at all levels (P

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Video Q&A: state-of-the-art therapy for the elite and non-elite athlete: an interview with Mike Carmont (2014)

Type of publication:
Journal article

Author(s):
*Carmont MR

Citation:
BMC Medicine, 2014, vol./is. 12/(8), 1741-7015;1741-7015 (2014)

Abstract:
In this video Q&A, Mr Mike Carmont answers questions about state-of-the-art treatments for elite athletes, and the progress and challenges behind translating these into successful therapies for the non-elite athlete.

Link to more details or full-text: http://europepmc.org/abstract/PMC/PMC3896799