Understanding the biomechanical risk factors ofpatellofemoral pain (PFP) in military individuals

Patellofemoral pain (PFP) is one of the major sources of chronic knee pain in young athletes,affecting one in four individuals. To progress further in this field, prospective studies aretherefore needed in order to gain a better understanding of the biomechanical risk factors ofPFP and to develop future treatment and prevention strategies. With this in mind, the mainpurpose of the present PhD thesis is to prospectively examine individuals’ lower limbmovements with two-dimensional (2D) video analysis and muscle strength with a handhelddynamometer (HHD) in order to screen for PFP development, in addition to other lower limbinjuries. Therefore, a systematic review and meta- analysis in addition to three studies wereconducted within this thesis to investigate the factors involved in the development of PFP. In the first study, 15 healthy subjects (6 male and 9 female) participated in a reliability study(within-day, between-day, intra-rater, and inter-rater reliability) of 2D frontal plane projectionangle (FPPA) and hip adduction (HADD) angle. They also participated in a validation studyfor 2D motion analysis against the gold standard of three-dimensional (3D) motion analysis.In the second study, eight healthy male subjects participated in a between-day reliability andvalidity study for 2D analysis and HHD strength tests against the gold standard of 3D analysis,using Qualysis Track Manager (QTM) system and an isokinetic dynamometer for themeasurements of lower limb kinematics (FPPA, Q-angle, HADD, knee flexion, ankledorsiflexion, and rearfoot angle) and strength (hip abductors and knee extensors). The mainstudy was undertaken with 315 healthy male infantry cadets and recruits from King Abdul-Aziz Military Academy (KAMA) and two other basic military training centres in Saudi Arabia.Lower limb kinematics and muscle strength were measured during running (RUN), single legsquatting (SLS), and single leg landing (SLL) in the first week of training, and were followedup over the participants’ 12 weeks of basic military training for the occurrence of PFP andother lower limb injuries. Participants who developed PFP had a significantly greater FPPA and Q-angle during SLS,SLL, and RUN, as well as a significantly greater HADD during SLS and SLL, than participantswho did not develop PFP. In addition, the injured group had significantly lower knee extensorand hip abductor muscle strength during the baseline assessment when compared to the noninjuredgroup. The logistic regression revealed that FPPA during SLL significantly predicts thedevelopment of PFP. Therefore, this appears to be a suitable method for screening of PFP riskbefore joining basic military training.

Level dc:type.qualificationlevel

Doctoral (Level 8)

Year dc:date.issued

2026

Author dc:creator

• Alrayani, HHA

Language dc:language

en

Identifier

oai:salford-repository.worktribe.com:1378704

OAI identifier oai:identifier

oai:salford-repository.worktribe.com:1378704