European Journal of Applied Physiology

, Volume 119, Issue 3, pp 735–742 | Cite as

Jumper’s knee mechanical consequences in professional basketball players: the “Camel’s Back curve”

  • Marc Dauty
  • Pierre Menu
  • Thomas Garraud
  • Olivier Mesland
  • Thibaud Berlivet
  • Benoit Metayer
  • Alban Fouasson-ChaillouxEmail author
Original Article



Jumper’s knee is characterized by an anterior knee pain during tendon palpation and can be classified in overuse pathologies, secondary to repetitive jumps. The prevalence is high in professional basketball players. It is responsible for an alteration of the motor control inducing a strength deficit of the quadriceps. We aimed to describe an isokinetic curve anomaly, a double-humped curve called “Camel’s Back curve”, consequence of a jumper’s knee history.


170 Professional basketball players were enrolled (24.8 ± 4.6 years; 91.8 ± 12.0 kg, 194 ± 9.0 cm). All players performed isokinetic tests of the knee extensors on a concentric mode at the angular speed of 60°/s and 180°/s.


43 players had a jumper’s knee history and 35 (81%) had a “Camel’s Back curve” at 60°/s. The sensitivity and the specificity of this curve were 81.3% and 100%, respectively. The minimum torque of strength was decreased from 12 to 18% compared to the 2 maximal peaks. Yet, the strength measured every 5° of ROM was significantly different between the players with “Camel’s Back curve” and those with normal curve.


“Camel’s Back curve” had never been described in that context. It may be secondary to a protective inhibitory mechanism which could alter jumping. The presence of a “Camel’s Back curve” would enable clinicians to adapt physical preparation, knee rehabilitation, and trainings to improve players performances.


Patellar tendon Jump Quadriceps Basketball Isokinetic 



Analysis of variance


Limb symmetry index


Physical medicine and rehabilitation


Range of motion


Author contributions

All authors conceived and designed the research protocol, read and approved the final manuscript. MD conducted experiments and analyzed the data. MD and AFC wrote the manuscript.

Compliance with ethical standards

Ethical approval

Applicable institutional and governmental regulations concerning ethics were followed during this research. The data report form was declared to the French data protection authority (Commission Nationale de l’Informatique et des Libertés) and to the Research Department of the University Hospital under the registration number RC18_0025. Since data were collected retrospectively and that patients’ management had not been modified, according to the French law, this study did not need to be approved by a research ethics committee (articles L.1121-1 paragraph 1 and R1121-2, Public Health code).

Conflict of interest

The authors have no conflict of interest to declare.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Physical Medicine and Rehabilitation DepartmentCHU Nantes, Hôpital Saint JacquesNantes Cedex 03France
  2. 2.Sports Medicine DepartmentCHU Nantes, Hôpital Saint JacquesNantes Cedex 03France
  3. 3.Inserm, UMR 1229, RMeS, Regenerative Medicine and SkeletonUniversité de Nantes, ONIRISNantesFrance
  4. 4.Rheumatologic DepartmentCHU NantesNantes CedexFrance
  5. 5.MPR Locomotrice et Respiratoire, CHU de NantesHôpital St JacquesNantes Cedex 1France

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