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Orthopedic management of the extremities in patients with Morquio A syndrome.

White KK, Jester A, Bache CE, Harmatz PR, Shediac R, Thacker MM, Mackenzie WG - J Child Orthop (2014)

Bottom Line: While the spinal manifestations of the disorder have received considerable attention in the literature, there have been few reported studies to date to guide the management of the orthopedic problems associated with the lower and upper extremities.Recommendations were further refined until consensus was reached.Key issues, including the importance of early diagnosis and the implications of medical therapy, are also addressed.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedic Surgery and Sports Medicine, Seattle Children's Hospital, University of Washington, Seattle, WA, USA, klane.white@seattlechildrens.org.

ABSTRACT

Background: Musculoskeletal involvement in Morquio A syndrome (mucopolysaccharidosis IVA; MPS IVA) contributes significantly to morbidity and mortality. While the spinal manifestations of the disorder have received considerable attention in the literature, there have been few reported studies to date to guide the management of the orthopedic problems associated with the lower and upper extremities.

Purpose: The objective was to develop recommendations for the management of the extremities in patients with Morquio A syndrome.

Methods: A group of specialists in orthopedics, pediatrics and genetics with experience in the management of Morquio A patients convened to review and discuss current clinical practices and to develop preliminary recommendations. Evidence from the literature was retrieved. Recommendations were further refined until consensus was reached.

Results and conclusions: This present article provides a detailed review and discussion of the lower and upper extremity deformities in Morquio A syndrome and presents recommendations for the assessment and treatment of these complications. Key issues, including the importance of early diagnosis and the implications of medical therapy, are also addressed. The recommendations herein represent an attempt to develop a uniform and practical approach to managing patients with Morquio A syndrome and improving their outcomes.

No MeSH data available.


Related in: MedlinePlus

Malalignment of the knee joint alters the biomechanics of gait in patients with Morquio A syndrome. Knee valgus causes the ground reaction force to be shifted laterally, which forces the knee into further valgus. The degree of genu valgum may be estimated by the quadriceps angle, or Q angle (the angle formed by a line drawn from the anterior superior iliac spine through the center of the patella and a line drawn from the center of the patella to the center of the tibial tubercle). Multiple anatomical factors contribute to the magnitude of the Q angle, including hip rotation, tibial torsion and foot position
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Fig3: Malalignment of the knee joint alters the biomechanics of gait in patients with Morquio A syndrome. Knee valgus causes the ground reaction force to be shifted laterally, which forces the knee into further valgus. The degree of genu valgum may be estimated by the quadriceps angle, or Q angle (the angle formed by a line drawn from the anterior superior iliac spine through the center of the patella and a line drawn from the center of the patella to the center of the tibial tubercle). Multiple anatomical factors contribute to the magnitude of the Q angle, including hip rotation, tibial torsion and foot position

Mentions: Reduced speed, cadence and stride length are primary gait abnormalities associated with Morquio A syndrome [28]. Lower extremity malalignment, muscle weakness and joint laxity contribute to the pathological gait pattern. Knee valgus causes the ground reaction force to be shifted laterally, which forces the knee into further valgus (Fig. 3). The extensor mechanism may subluxate laterally, resulting in reduced extensor mechanism moment arm. In severe cases, the ground reaction force moves behind the center of the rotation, necessitating quadriceps activity throughout stance phase, and may cause a flexion contracture of the knee. As individuals develop progressive genu valgum and subluxation of the extensor mechanism, there is a tendency for the tibia to follow into external rotation. This results in further reduction in power generation at the ankle. Eventually, the mechanics become so abnormal and power generation so poor that individuals cease ambulating.Fig. 3


Orthopedic management of the extremities in patients with Morquio A syndrome.

White KK, Jester A, Bache CE, Harmatz PR, Shediac R, Thacker MM, Mackenzie WG - J Child Orthop (2014)

Malalignment of the knee joint alters the biomechanics of gait in patients with Morquio A syndrome. Knee valgus causes the ground reaction force to be shifted laterally, which forces the knee into further valgus. The degree of genu valgum may be estimated by the quadriceps angle, or Q angle (the angle formed by a line drawn from the anterior superior iliac spine through the center of the patella and a line drawn from the center of the patella to the center of the tibial tubercle). Multiple anatomical factors contribute to the magnitude of the Q angle, including hip rotation, tibial torsion and foot position
© Copyright Policy - OpenAccess
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4128951&req=5

Fig3: Malalignment of the knee joint alters the biomechanics of gait in patients with Morquio A syndrome. Knee valgus causes the ground reaction force to be shifted laterally, which forces the knee into further valgus. The degree of genu valgum may be estimated by the quadriceps angle, or Q angle (the angle formed by a line drawn from the anterior superior iliac spine through the center of the patella and a line drawn from the center of the patella to the center of the tibial tubercle). Multiple anatomical factors contribute to the magnitude of the Q angle, including hip rotation, tibial torsion and foot position
Mentions: Reduced speed, cadence and stride length are primary gait abnormalities associated with Morquio A syndrome [28]. Lower extremity malalignment, muscle weakness and joint laxity contribute to the pathological gait pattern. Knee valgus causes the ground reaction force to be shifted laterally, which forces the knee into further valgus (Fig. 3). The extensor mechanism may subluxate laterally, resulting in reduced extensor mechanism moment arm. In severe cases, the ground reaction force moves behind the center of the rotation, necessitating quadriceps activity throughout stance phase, and may cause a flexion contracture of the knee. As individuals develop progressive genu valgum and subluxation of the extensor mechanism, there is a tendency for the tibia to follow into external rotation. This results in further reduction in power generation at the ankle. Eventually, the mechanics become so abnormal and power generation so poor that individuals cease ambulating.Fig. 3

Bottom Line: While the spinal manifestations of the disorder have received considerable attention in the literature, there have been few reported studies to date to guide the management of the orthopedic problems associated with the lower and upper extremities.Recommendations were further refined until consensus was reached.Key issues, including the importance of early diagnosis and the implications of medical therapy, are also addressed.

View Article: PubMed Central - PubMed

Affiliation: Department of Orthopaedic Surgery and Sports Medicine, Seattle Children's Hospital, University of Washington, Seattle, WA, USA, klane.white@seattlechildrens.org.

ABSTRACT

Background: Musculoskeletal involvement in Morquio A syndrome (mucopolysaccharidosis IVA; MPS IVA) contributes significantly to morbidity and mortality. While the spinal manifestations of the disorder have received considerable attention in the literature, there have been few reported studies to date to guide the management of the orthopedic problems associated with the lower and upper extremities.

Purpose: The objective was to develop recommendations for the management of the extremities in patients with Morquio A syndrome.

Methods: A group of specialists in orthopedics, pediatrics and genetics with experience in the management of Morquio A patients convened to review and discuss current clinical practices and to develop preliminary recommendations. Evidence from the literature was retrieved. Recommendations were further refined until consensus was reached.

Results and conclusions: This present article provides a detailed review and discussion of the lower and upper extremity deformities in Morquio A syndrome and presents recommendations for the assessment and treatment of these complications. Key issues, including the importance of early diagnosis and the implications of medical therapy, are also addressed. The recommendations herein represent an attempt to develop a uniform and practical approach to managing patients with Morquio A syndrome and improving their outcomes.

No MeSH data available.


Related in: MedlinePlus